diff --git a/.vs/Haedal_AlgorithmStudy/v17/.wsuo b/.vs/Haedal_AlgorithmStudy/v17/.wsuo
new file mode 100644
index 0000000..6129296
Binary files /dev/null and b/.vs/Haedal_AlgorithmStudy/v17/.wsuo differ
diff --git a/.vs/slnx.sqlite b/.vs/slnx.sqlite
new file mode 100644
index 0000000..a67645e
Binary files /dev/null and b/.vs/slnx.sqlite differ
diff --git a/HHNAM/11to20/11.py b/HHNAM/11to20/11.py
new file mode 100644
index 0000000..f286663
--- /dev/null
+++ b/HHNAM/11to20/11.py
@@ -0,0 +1,11 @@
+def solution(s):
+ stack = [ ]
+ for c in s:
+ if stack and stack[-1] == c:
+ stack.pop( )
+ else:
+ stack.append(c)
+ return int(not stack)
+
+# print(solution('baabaa'))
+# print(solution('cdcd'))
\ No newline at end of file
diff --git a/HHNAM/11to20/12.py b/HHNAM/11to20/12.py
new file mode 100644
index 0000000..53042ab
--- /dev/null
+++ b/HHNAM/11to20/12.py
@@ -0,0 +1,16 @@
+def solution(prices):
+ n = len(prices)
+ answer = [0] * n
+
+ stack = [0]
+ for i in range(1, n):
+ while stack and prices[i] < prices[stack[-1]]:
+ j = stack.pop( )
+ answer[j] = i - j
+ stack.append(i)
+ while stack:
+ j = stack.pop( )
+ answer[j] = n - 1 - j
+ return answer
+
+# print(solution([1,2,4,2,3]))
\ No newline at end of file
diff --git a/HHNAM/11to20/13.py b/HHNAM/11to20/13.py
new file mode 100644
index 0000000..b6986e8
--- /dev/null
+++ b/HHNAM/11to20/13.py
@@ -0,0 +1,27 @@
+def solution(board, moves):
+ lanes = [[ ] for _ in range(len(board[0]))]
+
+ for i in range(len(board) - 1, -1, -1):
+ for j in range(len(board[0])):
+ if board[i][j]:
+ lanes[j].append(board[i][j])
+
+ bucket = [ ]
+
+ answer = 0
+
+ for m in moves:
+ if lanes[m - 1]:
+ doll = lanes[m - 1].pop( )
+
+ if bucket and bucket[-1] == doll:
+ bucket.pop( )
+ answer += 2
+ else:
+ bucket.append(doll)
+
+ return answer
+
+# board = [[0,0,0,0,0],[0,0,1,0,3],[0,2,5,0,1],[4,2,4,4,2],[3,5,1,3,1]]
+# moves = [1,5,3,5,1,2,1,4]
+# print(solution(board, moves))
\ No newline at end of file
diff --git a/HHNAM/11to20/14.py b/HHNAM/11to20/14.py
new file mode 100644
index 0000000..7cc4cc7
--- /dev/null
+++ b/HHNAM/11to20/14.py
@@ -0,0 +1,39 @@
+def solution(n, k, cmd):
+ deleted = [ ]
+
+ up = [i - 1 for i in range(n + 2)]
+
+ down = [i + 1 for i in range(n + 1)]
+
+ k += 1
+
+ for cmd_i in cmd:
+ if cmd_i.startswith("C"):
+ deleted.append(k)
+ up[down[k]] = up[k]
+ down[up[k]] = down[k]
+ k = up[k] if n < down[k] else down[k]
+
+ elif cmd_i.startswith("Z"):
+ restore = deleted.pop( )
+ down[up[restore]] = restore
+ up[down[restore]] = restore
+
+ else:
+ action, num = cmd_i.split( )
+ if action == "U":
+ for _ in range(int(num)):
+ k = up[k]
+ else:
+ for _ in range(int(num)):
+ k = down[k]
+
+ answer = ["O"] * n
+ for i in deleted:
+ answer[i - 1] = "X"
+ return "".join(answer)
+
+# n = 8
+# k = 2
+# cmd = ['D 2', 'C', 'U 3', 'C', 'D 4', 'C', 'U 2', 'Z', 'Z']
+# print(solution(n,k,cmd))
\ No newline at end of file
diff --git a/HHNAM/11to20/15.py b/HHNAM/11to20/15.py
new file mode 100644
index 0000000..da2d5f6
--- /dev/null
+++ b/HHNAM/11to20/15.py
@@ -0,0 +1,12 @@
+from collections import deque
+
+def solution(N, K):
+ queue = deque(range(1, N+1))
+
+ while len(queue) > 1:
+ for _ in range(K-1):
+ queue.append(queue.popleft())
+ queue.popleft()
+ return queue[0]
+
+# print(solution(5,2))
\ No newline at end of file
diff --git a/HHNAM/11to20/16.py b/HHNAM/11to20/16.py
new file mode 100644
index 0000000..21015f1
--- /dev/null
+++ b/HHNAM/11to20/16.py
@@ -0,0 +1,24 @@
+import math
+
+def solution(progresses, speeds):
+ answer = [ ]
+ n = len(progresses)
+ days_left = [math.ceil((100 - progresses[i]) / speeds[i]) for i in range(n)]
+
+ count = 0
+ max_day = days_left[0]
+
+ for i in range(n):
+ if days_left[i] <= max_day:
+ count += 1
+ else:
+ answer.append(count)
+ count = 1
+ max_day = days_left[i]
+
+ answer.append(count)
+ return answer
+
+# progresses = [93,30,55]
+# speeds = [1,30,5]
+# print(solution(progresses, speeds))
\ No newline at end of file
diff --git a/HHNAM/11to20/17.py b/HHNAM/11to20/17.py
new file mode 100644
index 0000000..91125d4
--- /dev/null
+++ b/HHNAM/11to20/17.py
@@ -0,0 +1,23 @@
+from collections import deque
+
+def solution(cards1, cards2, goal):
+ cards1 = deque(cards1)
+ cards2 = deque(cards2)
+ goal = deque(goal)
+
+ while goal:
+ if cards1 and cards1[0] == goal[0]:
+ cards1.popleft()
+ goal.popleft()
+ elif cards2 and cards2[0] == goal[0]:
+ cards2.popleft()
+ goal.popleft()
+ else:
+ break
+
+ return "Yes" if not goal else "No"
+
+# cards1 = ['i', 'drink', 'water']
+# cards2 = ['want', 'to']
+# goal = ['i', 'want', 'to', 'drink', 'water']
+# print(solution(cards1, cards2, goal))
diff --git a/HHNAM/11to20/18.py b/HHNAM/11to20/18.py
new file mode 100644
index 0000000..b2edf94
--- /dev/null
+++ b/HHNAM/11to20/18.py
@@ -0,0 +1,24 @@
+def count_sort(arr, k):
+ hashtable = [0] * (k + 1)
+
+ for num in arr:
+ if num <= k:
+ hashtable[num] = 1
+ return hashtable
+
+def solution(arr, target):
+ hashtable = count_sort(arr, target)
+
+ for num in arr:
+ complement = target - num
+ if (
+ complement != num
+ and complement >= 0
+ and complement <= target
+ and hashtable[complement] == 1
+ ):
+ return True
+ return False
+
+# print(solution([1, 2, 3, 4, 8], 6))
+# print(solution([2, 3, 5, 9], 10))
\ No newline at end of file
diff --git a/HHNAM/11to20/19.py b/HHNAM/11to20/19.py
new file mode 100644
index 0000000..95716a0
--- /dev/null
+++ b/HHNAM/11to20/19.py
@@ -0,0 +1,21 @@
+def polynomial_hash(str):
+ p = 31
+ m = 1_000_000_007
+ hash_value = 0
+ for char in str:
+ hash_value = (hash_value * p + ord(char)) % m
+ return hash_value
+
+def solution(string_list, query_list):
+ hash_list = [polynomial_hash(str) for str in string_list]
+
+ result = [ ]
+ for query in query_list:
+ query_hash = polynomial_hash(query)
+ if query_hash in hash_list:
+ result.append(True)
+ else:
+ result.append(False)
+ return result
+
+# print(solution(["apple", "banana", "cherry"], ["banana", "kiwi", "melon", "apple"] ))
\ No newline at end of file
diff --git a/HHNAM/11to20/20.py b/HHNAM/11to20/20.py
new file mode 100644
index 0000000..3683fdd
--- /dev/null
+++ b/HHNAM/11to20/20.py
@@ -0,0 +1,19 @@
+def solution(participant, completion):
+ dic = { }
+
+ for p in participant:
+ if p in dic:
+ dic[p] += 1
+ else:
+ dic[p] = 1
+
+ for c in completion:
+ dic[c] -= 1
+
+ for key in dic.keys( ) :
+ if dic[key] > 0:
+ return key
+
+# participant = ['leo', 'kiki', 'eden']
+# completion = ['eden', 'kiki']
+# print(solution(participant, completion))
\ No newline at end of file
diff --git a/HHNAM/1to10/10.py b/HHNAM/1to10/10.py
new file mode 100644
index 0000000..bf11963
--- /dev/null
+++ b/HHNAM/1to10/10.py
@@ -0,0 +1,31 @@
+def solution(s):
+ answer = 0
+ n = len(s)
+ for i in range(n):
+ stack = [ ]
+ for j in range(n):
+ c = s[(i + j) % n]
+ if c == "(" or c == "[" or c == "{":
+ stack.append(c)
+ else:
+ if not stack:
+ break
+
+ if c == ")" and stack[-1] == "(":
+ stack.pop( )
+ elif c == "]" and stack[-1] == "[":
+ stack.pop( )
+ elif c == "}" and stack[-1] == "{":
+ stack.pop( )
+ else:
+ break
+ else:
+ if not stack:
+ answer += 1
+ return answer
+
+
+# print(solution('[](){}'))
+# print(solution('}]()[{'))
+# print(solution('[)(]'))
+# print(solution('}}}'))
\ No newline at end of file
diff --git a/HHNAM/1to10/4.py b/HHNAM/1to10/4.py
index 873ed44..70e0189 100644
--- a/HHNAM/1to10/4.py
+++ b/HHNAM/1to10/4.py
@@ -19,5 +19,5 @@ def solution(answers):
highest_scores.append(i+1)
return highest_scores
-print(solution([1,2,3,4,5]))
-print(solution([1,3,2,4,2]))
+# print(solution([1,2,3,4,5]))
+# print(solution([1,3,2,4,2]))
diff --git a/HHNAM/1to10/5.py b/HHNAM/1to10/5.py
new file mode 100644
index 0000000..dbad7e4
--- /dev/null
+++ b/HHNAM/1to10/5.py
@@ -0,0 +1,15 @@
+def solution(arr1, arr2):
+ r1, c1 = len(arr1), len(arr1[0])
+ r2, c2 = len(arr2), len(arr2[0])
+
+ ret = [[0] * c2 for _ in range(r1)]
+
+ for i in range(r1):
+ for j in range(c2):
+ for k in range(c1):
+ ret[i][j] += arr1[i][k] * arr2[k][j]
+ return ret
+
+# arr1 = [[1,4],[3,2],[4,1]]
+# arr2 = [[3,3],[3,3]]
+# print(solution(arr1, arr2))
\ No newline at end of file
diff --git a/HHNAM/1to10/6.py b/HHNAM/1to10/6.py
new file mode 100644
index 0000000..52f9470
--- /dev/null
+++ b/HHNAM/1to10/6.py
@@ -0,0 +1,22 @@
+def solution(N, stages):
+ challenger = [0] * (N + 2)
+ for stage in stages:
+ challenger[stage] += 1
+
+ fails = { }
+ total = len(stages)
+
+ for i in range(1, N + 1):
+ if challenger[i] == 0 :
+ fails[i] = 0
+ else:
+ fails[i] = challenger[i] / total
+ total -= challenger[i]
+
+ result = sorted(fails, key=lambda x : fails[x], reverse=True)
+
+ return result
+
+N = 5
+stages = [2,1,2,6,2,4,3,3]
+print(solution(N, stages))
\ No newline at end of file
diff --git a/HHNAM/1to10/7.py b/HHNAM/1to10/7.py
new file mode 100644
index 0000000..4a091e5
--- /dev/null
+++ b/HHNAM/1to10/7.py
@@ -0,0 +1,28 @@
+def is_valid_move(nx, ny) :
+ return 0 <= nx < 11 and 0 <= ny < 11
+
+def update_location(x, y, dir) :
+ if dir == 'U':
+ nx, ny = x, y + 1
+ elif dir == 'D':
+ nx, ny = x, y - 1
+ elif dir == 'L':
+ nx, ny = x - 1, y
+ elif dir == 'R':
+ nx, ny = x + 1, y
+ return nx, ny
+
+def solution(dirs):
+ x, y = 5, 5
+ ans = set( )
+ for dir in dirs :
+ nx, ny = update_location(x, y, dir)
+ if not is_valid_move(nx, ny) :
+ continue
+ ans.add((x, y, nx, ny))
+ ans.add((nx, ny, x, y))
+ x, y = nx, ny
+ return len(ans)/2
+
+# dirs = 'ULURRDLLU'
+# print(solution(dirs))
\ No newline at end of file
diff --git a/HHNAM/1to10/8.py b/HHNAM/1to10/8.py
new file mode 100644
index 0000000..481679d
--- /dev/null
+++ b/HHNAM/1to10/8.py
@@ -0,0 +1,18 @@
+def solution(s):
+ stack = [ ]
+ for c in s:
+ if c == "(":
+ stack.append(c)
+ elif c == ")":
+ if not stack:
+ return False
+ else:
+ stack.pop( )
+ if stack:
+ return False
+ else:
+ return True
+
+
+# print(solution('(())()'))
+# print(solution('((())()'))
\ No newline at end of file
diff --git a/HHNAM/1to10/9.py b/HHNAM/1to10/9.py
new file mode 100644
index 0000000..d552b2c
--- /dev/null
+++ b/HHNAM/1to10/9.py
@@ -0,0 +1,13 @@
+def solution(decimal):
+ stack = []
+ while decimal > 0:
+ remainder = decimal % 2
+ stack.append(str(remainder))
+ decimal //= 2
+ stack.reverse()
+ return ''.join(stack)
+
+
+# print(solution(10))
+# print(solution(27))
+# print(solution(12345))
\ No newline at end of file
diff --git a/HHNAM/21to30/21.py b/HHNAM/21to30/21.py
new file mode 100644
index 0000000..362a73e
--- /dev/null
+++ b/HHNAM/21to30/21.py
@@ -0,0 +1,18 @@
+def solution(want, number, discount):
+ want_dict = { }
+ for i in range(len(want)):
+ want_dict[want[i]] = number[i]
+
+ answer = 0
+
+ for i in range(len(discount) - 9):
+ discount_10d = { }
+
+ for j in range(i, i + 10):
+ if discount[j] in want_dict:
+ discount_10d[discount[j]] = discount_10d.get(discount[j], 0) + 1
+
+ if discount_10d == want_dict:
+ answer += 1
+
+ return answer
diff --git a/HHNAM/21to30/22.py b/HHNAM/21to30/22.py
new file mode 100644
index 0000000..20a3449
--- /dev/null
+++ b/HHNAM/21to30/22.py
@@ -0,0 +1,16 @@
+def solution(record):
+ answer = [ ]
+ uid = { }
+ for line in record:
+ cmd = line.split(" ")
+ if cmd[0] != "Leave":
+ uid[cmd[1]] = cmd[2]
+ for line in record:
+ cmd = line.split(" ")
+ if cmd[0] == "Enter":
+ answer.append("%s님이 들어왔습니다." % uid[cmd[1]])
+ elif cmd[0] == "Change":
+ pass
+ else:
+ answer.append("%s님이 나갔습니다." % uid[cmd[1]])
+ return answer
diff --git a/HHNAM/21to30/23.py b/HHNAM/21to30/23.py
new file mode 100644
index 0000000..f1355ca
--- /dev/null
+++ b/HHNAM/21to30/23.py
@@ -0,0 +1,21 @@
+def solution(genres, plays):
+ answer = [ ]
+ genres_dict = { }
+ play_dict = { }
+
+ for i in range(len(genres)):
+ genre = genres[i]
+ play = plays[i]
+ if genre not in genres_dict:
+ genres_dict[genre] = [ ]
+ play_dict[genre] = 0
+ genres_dict[genre].append((i, play))
+ play_dict[genre] += play
+
+ sorted_genres = sorted(play_dict.items( ) , key=lambda x: x[1], reverse=True)
+
+ for genre, _ in sorted_genres:
+ sorted_songs = sorted(genres_dict[genre], key=lambda x: (-x[1], x[0]))
+ answer.extend([idx for idx, _ in sorted_songs[:2]])
+
+ return answer
\ No newline at end of file
diff --git a/HHNAM/21to30/24.py b/HHNAM/21to30/24.py
new file mode 100644
index 0000000..d68edc7
--- /dev/null
+++ b/HHNAM/21to30/24.py
@@ -0,0 +1,22 @@
+def solution(id_list, report, k):
+ reported_user = { }
+ count = { }
+ for r in report:
+ user_id, reported_id = r.split( )
+ if reported_id not in reported_user:
+ reported_user[reported_id] = set( )
+ reported_user[reported_id].add(user_id)
+ for reported_id, user_id_lst in reported_user.items( ) :
+ if len(user_id_lst) >= k:
+ for uid in user_id_lst:
+ if uid not in count:
+ count[uid] = 1
+ else:
+ count[uid] += 1
+ answer = [ ]
+ for i in range(len(id_list)):
+ if id_list[i] not in count:
+ answer.append(0)
+ else:
+ answer.append(count[id_list[i]])
+ return answer
\ No newline at end of file
diff --git a/HHNAM/21to30/25.py b/HHNAM/21to30/25.py
new file mode 100644
index 0000000..d20aad6
--- /dev/null
+++ b/HHNAM/21to30/25.py
@@ -0,0 +1,19 @@
+from itertools import combinations
+from collections import Counter
+
+def solution(orders, course):
+ answer = [ ]
+
+ for c in course:
+ menu = [ ]
+ for order in orders:
+ comb = combinations(sorted(order), c)
+ menu += comb
+
+ counter = Counter(menu)
+ if (len(counter) != 0 and max(counter.values( ) ) != 1):
+ for m, cnt in counter.items( ) :
+ if cnt == max(counter.values( ) ):
+ answer.append("".join(m))
+
+ return sorted(answer)
\ No newline at end of file
diff --git a/HHNAM/21to30/26.py b/HHNAM/21to30/26.py
new file mode 100644
index 0000000..f087689
--- /dev/null
+++ b/HHNAM/21to30/26.py
@@ -0,0 +1,33 @@
+def preorder(nodes, idx):
+ if idx < len(nodes):
+ ret = str(nodes[idx]) + " "
+ ret += preorder(nodes, idx * 2 + 1)
+ ret += preorder(nodes, idx * 2 + 2)
+ return ret
+ else:
+ return ""
+
+def inorder(nodes, idx):
+ if idx < len(nodes):
+ ret = inorder(nodes, idx * 2 + 1)
+ ret += str(nodes[idx]) + " "
+ ret += inorder(nodes, idx * 2 + 2)
+ return ret
+ else:
+ return ""
+
+def postorder(nodes, idx):
+ if idx < len(nodes):
+ ret = postorder(nodes, idx * 2 + 1)
+ ret += postorder(nodes, idx * 2 + 2)
+ ret += str(nodes[idx]) + " "
+ return ret
+ else:
+ return ""
+
+def solution(nodes):
+ return [
+ preorder(nodes,0)[:-1],
+ inorder(nodes,0)[:-1],
+ postorder(nodes,0)[:-1],
+ ]
\ No newline at end of file
diff --git a/HHNAM/21to30/27.py b/HHNAM/21to30/27.py
new file mode 100644
index 0000000..8ad58e2
--- /dev/null
+++ b/HHNAM/21to30/27.py
@@ -0,0 +1,50 @@
+class Node:
+ def __init__(self, key):
+ self.left = None
+ self.right = None
+ self.val = key
+
+class BST:
+ def __init__(self):
+ self.root = None
+ def insert(self, key):
+ if not self.root:
+ self.root = Node(key)
+ else:
+ curr = self.root
+ while True:
+ if key < curr.val:
+ if curr.left:
+ curr = curr.left
+ else:
+ curr.left = Node(key)
+ break
+ else:
+ if curr.right:
+ curr = curr.right
+ else:
+ curr.right = Node(key)
+ break
+ def search(self, key):
+ curr = self.root
+ while curr and curr.val != key:
+ if key < curr.val:
+ curr = curr.left
+ else:
+ curr = curr.right
+ return curr
+def solution(lst, search_lst):
+ bst = BST()
+ for key in lst:
+ bst.insert(key)
+ result = []
+ for search_val in search_lst:
+ if bst.search(search_val):
+ result.append(True)
+ else:
+ result.append(False)
+ return result
+
+
+# print(solution([5, 3, 8, 4, 2, 1, 7, 10], [1, 2, 5, 6])) # [True, True, True, False]
+# print(solution([1, 3, 5, 7, 9], [2, 4, 6, 8, 10])) # [False, False, False, False, False]
\ No newline at end of file
diff --git a/HHNAM/21to30/28.py b/HHNAM/21to30/28.py
new file mode 100644
index 0000000..c52c5eb
--- /dev/null
+++ b/HHNAM/21to30/28.py
@@ -0,0 +1,7 @@
+def solution(n, a, b):
+ answer = 0
+ while a != b:
+ a = (a + 1) // 2
+ b = (b + 1) // 2
+ answer += 1
+ return answer
\ No newline at end of file
diff --git a/HHNAM/21to30/29.py b/HHNAM/21to30/29.py
new file mode 100644
index 0000000..0bf0d45
--- /dev/null
+++ b/HHNAM/21to30/29.py
@@ -0,0 +1,14 @@
+def solution(enroll, referral, seller, amount):
+ parent = dict(zip(enroll, referral))
+
+ total = {name: 0 for name in enroll}
+
+ for i in range(len(seller)):
+ money = amount[i] * 100
+ cur_name = seller[i]
+ while money > 0 and cur_name != "-":
+ total[cur_name] += money - money // 10
+ cur_name = parent[cur_name]
+ money //= 10
+
+ return [total[name] for name in enroll]
\ No newline at end of file
diff --git a/HHNAM/21to30/30.py b/HHNAM/21to30/30.py
new file mode 100644
index 0000000..5fe2f4e
--- /dev/null
+++ b/HHNAM/21to30/30.py
@@ -0,0 +1,43 @@
+from collections import deque
+
+def is_valid_move(ny, nx, n, m, maps):
+ return 0 <= ny < n and 0 <= nx < m and maps[ny][nx] != "X"
+
+def append_to_queue(ny, nx, k, time, visited, q):
+ if not visited[ny][nx][k]:
+ visited[ny][nx][k] = True
+ q.append((ny, nx, k, time + 1))
+
+def solution(maps):
+ n, m = len(maps), len(maps[0])
+ visited = [[[False for _ in range(2)] for _ in range(m)] for _ in range(n)]
+ dy = [-1, 1, 0, 0]
+ dx = [0, 0, -1, 1]
+ q = deque( )
+ end_y, end_x = -1, -1
+
+ for i in range(n):
+ for j in range(m):
+ if maps[i][j] == "S":
+ q.append((i, j, 0, 0))
+ visited[i][j][0] = True
+ if maps[i][j] == "E":
+ end_y, end_x = i, j
+
+ while q:
+ y, x, k, time = q.popleft( )
+
+ if y == end_y and x == end_x and k == 1:
+ return time
+
+ for i in range(4):
+ ny, nx = y + dy[i], x + dx[i]
+ if not is_valid_move(ny, nx, n, m, maps):
+ continue
+
+ if maps[ny][nx] == "L":
+ append_to_queue(ny, nx, 1, time, visited, q)
+ else:
+ append_to_queue(ny, nx, k, time, visited, q)
+
+ return -1
\ No newline at end of file
diff --git a/HHNAM/31to40/31.py b/HHNAM/31to40/31.py
new file mode 100644
index 0000000..4f4bcf9
--- /dev/null
+++ b/HHNAM/31to40/31.py
@@ -0,0 +1,30 @@
+from collections import deque
+
+def solution(info, edges):
+ def build_tree(info, edges):
+ tree = [[] for _ in range(len(info))]
+ for edge in edges:
+ tree[edge[0]].append(edge[1])
+ return tree
+
+ tree = build_tree(info, edges)
+ max_sheep = 0
+
+ q = deque([(0, 1,0, set())])
+
+ while q:
+ current, sheep_count, wolf_count, visited = q.popleft()
+ max_sheep = max(max_sheep, sheep_count)
+ visited.update(tree[current])
+
+ for next_node in visited:
+ if info[next_node]:
+ if sheep_count != wolf_count + 1:
+ q.append(
+ (next_node, sheep_count, wolf_count + 1, visited - {next_node})
+ )
+ else:
+ q.append(
+ (next_node, sheep_count + 1, wolf_count, visited - {next_node})
+ )
+ return max_sheep
\ No newline at end of file
diff --git a/HHNAM/31to40/32.py b/HHNAM/31to40/32.py
new file mode 100644
index 0000000..48c5a07
--- /dev/null
+++ b/HHNAM/31to40/32.py
@@ -0,0 +1,69 @@
+from collections import deque
+
+class Node:
+ def __init__(self, info, num, left=None, right=None):
+ self.info = info
+ self.left = left
+ self.right = right
+ self.num = num
+
+ def has_left(self):
+ return self.left is not None
+
+ def has_right(self):
+ return self.right is not None
+
+def make_BT(nodeinfo):
+ nodes = [i for i in range(1, len(nodeinfo) + 1)]
+ nodes.sort(key=lambda x: (nodeinfo[x - 1][1], -nodeinfo[x - 1][0]), reverse=True)
+ root = None
+ for i in range(len(nodes)):
+ if root is None:
+ root = Node(nodeinfo[nodes[0] - 1], nodes[0])
+ else:
+ parent = root
+ node = Node(nodeinfo[nodes[i] - 1], nodes[i])
+ while True:
+ if node.info[0] < parent.info[0]:
+ if parent.has_left():
+ parent = parent.left
+ continue
+ parent.left = node
+ break
+ else:
+ if parent.has_right():
+ parent = parent.right
+ continue
+ parent.right = node
+ break
+ return root
+
+def pre_order(root, answer):
+ stack = [root]
+ while stack:
+ node = stack.pop()
+ if node is None:
+ continue
+ answer[0].append(node.num)
+ stack.append(node.right)
+ stack.append(node.left)
+
+def post_order(root, answer):
+ stack = [(root, False)]
+ while stack:
+ node, visited = stack.pop()
+ if node is None:
+ continue
+ if visited:
+ answer[1].append(node.num)
+ else:
+ stack.append((node, True))
+ stack.append((node.right, False))
+ stack.append((node.left, False))
+
+def solution(nodeinfo):
+ answer = [[], []]
+ root = make_BT(nodeinfo)
+ pre_order(root, answer)
+ post_order(root, answer)
+ return answer
\ No newline at end of file
diff --git a/HHNAM/31to40/33.py b/HHNAM/31to40/33.py
new file mode 100644
index 0000000..b7fede3
--- /dev/null
+++ b/HHNAM/31to40/33.py
@@ -0,0 +1,30 @@
+def find(parents, x):
+ if parents[x] == x:
+ return x
+ parents[x] = find(parents, parents[x])
+ return parents[x]
+
+
+def union(parents, x, y):
+ root1 = find(parents, x)
+ root2 = find(parents, y)
+
+ parents[root2] = root1
+
+def solution(k, operations):
+ parents = list(range(k))
+ n = k
+
+ for op in operations:
+ if op[0] == "u":
+ union(parents, op[1], op[2])
+ elif op[0] == "f":
+ find(parents, op[1])
+
+ n = len(set(find(parents, i) for i in range(k)))
+
+ return n
+
+
+# print(solution(3,[['u', 0, 1], ['u', 1, 2], ['f', 2]]))
+# print(solution(4,[['u', 0, 1], ['u', 2, 3], ['f', 0]]))
\ No newline at end of file
diff --git a/HHNAM/31to40/34.py b/HHNAM/31to40/34.py
new file mode 100644
index 0000000..081377b
--- /dev/null
+++ b/HHNAM/31to40/34.py
@@ -0,0 +1,5 @@
+def solution(nums):
+ num_set = set(nums)
+ n = len(nums)
+ k = n // 2
+ return min(k, len(num_set))
\ No newline at end of file
diff --git a/HHNAM/31to40/35.py b/HHNAM/31to40/35.py
new file mode 100644
index 0000000..36d2507
--- /dev/null
+++ b/HHNAM/31to40/35.py
@@ -0,0 +1,9 @@
+def solution(n, words):
+ used_words = set( )
+ prev_word = words[0][0]
+ for i, word in enumerate(words):
+ if word in used_words or word[0] != prev_word:
+ return [(i % n) + 1, (i // n) + 1]
+ used_words.add(word)
+ prev_word = word[-1]
+ return [0, 0]
\ No newline at end of file
diff --git a/HHNAM/31to40/36.py b/HHNAM/31to40/36.py
new file mode 100644
index 0000000..00c2ee1
--- /dev/null
+++ b/HHNAM/31to40/36.py
@@ -0,0 +1,8 @@
+def solution(phone_book):
+ phone_book.sort( )
+
+ for i in range(len(phone_book) - 1):
+ if phone_book[i + 1].startswith(phone_book[i]):
+ return False
+
+ return True
\ No newline at end of file
diff --git a/HHNAM/31to40/37.py b/HHNAM/31to40/37.py
new file mode 100644
index 0000000..4f263c7
--- /dev/null
+++ b/HHNAM/31to40/37.py
@@ -0,0 +1,40 @@
+def find(parent, i):
+ if parent[i] == i:
+ return i
+ parent[i] = find(parent, parent[i])
+ return parent[i]
+
+def union(parent, rank, x, y):
+ xroot = find(parent, x)
+ yroot = find(parent, y)
+
+ if rank[xroot] < rank[yroot]:
+ parent[xroot] = yroot
+ elif rank[xroot] > rank[yroot]:
+ parent[yroot] = xroot
+ else:
+ parent[yroot] = xroot
+ rank[xroot] += 1
+
+def solution(n, costs):
+ costs.sort(key=lambda x: x[2])
+
+ parent = [i for i in range(n)]
+ rank = [0] * n
+
+ min_cost = 0
+ edges = 0
+
+ for edge in costs:
+ if edges == n - 1:
+ break
+
+ x = find(parent, edge[0])
+ y = find(parent, edge[1])
+
+ if x != y:
+ union(parent, rank, x, y)
+ min_cost += edge[2]
+ edges += 1
+
+ return min_cost
\ No newline at end of file
diff --git a/HHNAM/31to40/38.py b/HHNAM/31to40/38.py
new file mode 100644
index 0000000..fb77b9e
--- /dev/null
+++ b/HHNAM/31to40/38.py
@@ -0,0 +1,21 @@
+from collections import defaultdict
+
+def solution(graph, start):
+ adj_list = defaultdict(list)
+ for u, v in graph:
+ adj_list[u].append(v)
+
+ def dfs(node, visited, result):
+ visited.add(node)
+ result.append(node)
+ for neighbor in adj_list.get(node, []):
+ if neighbor not in visited:
+ dfs(neighbor, visited, result)
+
+ visited = set()
+ result = []
+ dfs(start, visited, result)
+ return result
+
+# print(solution([['A', 'B'], ['B', 'C'], ['C', 'D'], ['D', 'E']], 'A'))
+# print(solution([['A', 'B'], ['A', 'C'], ['B', 'D'], ['B', 'E'], ['C', 'F'], ['E', 'F']], 'A'))
\ No newline at end of file
diff --git a/HHNAM/31to40/39.py b/HHNAM/31to40/39.py
new file mode 100644
index 0000000..624b6bc
--- /dev/null
+++ b/HHNAM/31to40/39.py
@@ -0,0 +1,28 @@
+from collections import defaultdict, deque
+
+def solution(graph, start):
+ adj_list = defaultdict(list)
+ for u, v in graph:
+ adj_list[u].append(v)
+
+ def bfs(start):
+ visited = set()
+
+ queue = deque([start])
+ visited.add(start)
+ result.append(start)
+
+ while queue:
+ node = queue.popleft()
+ for neighbor in adj_list.get(node, []):
+ if neighbor not in visited:
+ queue.append(neighbor)
+ visited.add(neighbor)
+ result.append(neighbor)
+
+ result = []
+ bfs(start)
+ return result
+
+# print(solution([(1, 2), (1, 3), (2, 4), (2, 5), (3, 6), (3, 7), (4, 8), (5, 8), (6, 9), (7, 9)],1))
+# print(solution([(0, 1), (1, 2), (2, 3), (3, 4), (4, 5), (5, 0)],1))
\ No newline at end of file
diff --git a/HHNAM/31to40/40.py b/HHNAM/31to40/40.py
new file mode 100644
index 0000000..749d7ca
--- /dev/null
+++ b/HHNAM/31to40/40.py
@@ -0,0 +1,30 @@
+import heapq
+
+def solution(graph, start):
+ distances = {node: float("inf") for node in graph}
+ distances[start] = 0
+ queue = []
+ heapq.heappush(queue, [distances[start], start])
+ paths = {start: [start]}
+ visited = set()
+
+ while queue:
+ current_distance, current_node = heapq.heappop(queue)
+ if current_node in visited:
+ continue
+ visited.add(current_node)
+
+ for adjacent_node, weight in graph[current_node].items():
+ distance = current_distance + weight
+ if distance < distances[adjacent_node]:
+ distances[adjacent_node] = distance
+ paths[adjacent_node] = paths[current_node] + [adjacent_node]
+ heapq.heappush(queue, [distance, adjacent_node])
+
+ sorted_paths = {node: paths[node] for node in sorted(paths)}
+
+ return [distances, sorted_paths]
+
+
+# print(solution({ 'A': {'B': 9, 'C': 3}, 'B': {'A': 5}, 'C': {'B': 1} }, 'A'))
+# print(solution({'A': {'B': 1}, 'B': {'C': 5}, 'C': {'D': 1}, 'D': {}}, 'A'))
\ No newline at end of file
diff --git a/HHNAM/41to50/41.py b/HHNAM/41to50/41.py
new file mode 100644
index 0000000..302a2e3
--- /dev/null
+++ b/HHNAM/41to50/41.py
@@ -0,0 +1,23 @@
+def solution(graph, source):
+ num_vertices = len(graph)
+
+ distance = [float("inf")] * num_vertices
+ distance[source] = 0
+
+ predecessor = [None] * num_vertices
+
+ for temp in range(num_vertices - 1):
+ for u in range(num_vertices):
+ for v, weight in graph[u]:
+ if distance[u] + weight < distance[v]:
+ distance[v] = distance[u] + weight
+ predecessor[v] = u
+
+ for u in range(num_vertices):
+ for v, weight in graph[u]:
+ if distance[u] + weight < distance[v]:
+ return [-1]
+ return [distance, predecessor]
+
+print(solution([[(1, 4), (2, 3), (4, -6 )], [(3, 5)], [(1, 2)], [(0, 7), (2, 4)],[(2, 2)]],0))
+print(solution([[(1, 5), (2, -1)], [(2, 2)], [(3, -2)], [(0, 2), (1, 6)]],0))
\ No newline at end of file
diff --git a/HHNAM/41to50/42.py b/HHNAM/41to50/42.py
new file mode 100644
index 0000000..3ca591a
--- /dev/null
+++ b/HHNAM/41to50/42.py
@@ -0,0 +1,35 @@
+from collections import deque
+
+def solution(maps):
+ move = [[-1, 0], [0, -1], [0, 1], [1, 0]]
+
+ n = len(maps)
+ m = len(maps[0])
+
+ dist = [[-1] * m for _ in range(n)]
+
+ def bfs(start):
+ q = deque([start])
+ dist[start[0]][start[1]] = 1
+
+ while q:
+ here = q.popleft()
+
+ for direct in move:
+ row, column = here[0] + direct[0], here[1] + direct[1]
+
+ if row < 0 or row >= n or column < 0 or column >= m:
+ continue
+
+ if maps[row][column] == 0:
+ continue
+
+ if dist[row][column] == -1:
+ q.append([row, column])
+ dist[row][column] = dist[here[0]][here[1]] + 1
+
+ return dist
+
+ bfs([0, 0])
+
+ return dist[n - 1][m - 1]
\ No newline at end of file
diff --git a/HHNAM/41to50/43.py b/HHNAM/41to50/43.py
new file mode 100644
index 0000000..54472e2
--- /dev/null
+++ b/HHNAM/41to50/43.py
@@ -0,0 +1,14 @@
+def dfs(computers, visited, node):
+ visited[node] = True
+ for idx, connected in enumerate(computers[node]):
+ if connected and not visited[idx]:
+ dfs(computers, visited, idx)
+
+def solution(n, computers):
+ answer = 0
+ visited = [False] * n
+ for i in range(n):
+ if not visited[i]:
+ dfs(computers, visited, i)
+ answer += 1
+ return answer
\ No newline at end of file
diff --git a/HHNAM/41to50/44.py b/HHNAM/41to50/44.py
new file mode 100644
index 0000000..2524942
--- /dev/null
+++ b/HHNAM/41to50/44.py
@@ -0,0 +1,23 @@
+import heapq
+
+def solution(N, road, K):
+ graph = [[] for _ in range(N + 1)]
+ distances = [float("inf")] * (N + 1)
+ distances[1] = 0
+
+ for a, b, cost in road:
+ graph[a].append((b, cost))
+ graph[b].append((a, cost))
+
+ heap = []
+ heapq.heappush(heap, (0, 1))
+ while heap:
+ dist, node = heapq.heappop(heap)
+
+ for next_node, next_dist in graph[node]:
+ cost = dist + next_dist
+ if cost < distances[next_node]:
+ distances[next_node] = cost
+ heapq.heappush(heap, (cost, next_node))
+
+ return sum(1 for dist in distances if dist <= K)
\ No newline at end of file
diff --git a/HHNAM/41to50/45.py b/HHNAM/41to50/45.py
new file mode 100644
index 0000000..f76d5e7
--- /dev/null
+++ b/HHNAM/41to50/45.py
@@ -0,0 +1,40 @@
+def solution(board):
+ def is_valid(x, y):
+ return 0 <= x < N and 0 <= y < N
+
+ def is_blocked(x, y):
+ return (x, y) == (0, 0) or not is_valid(x, y) or board[x][y] == 1
+
+ def calculate_cost(direction, prev_direction, cost):
+ if prev_direction == -1 or (prev_direction - direction) % 2 == 0:
+ return cost + 100
+ else:
+ return cost + 600
+
+ def isShouldUpdate(x, y, direction, new_cost):
+ return visited[x][y][direction] == 0 or visited[x][y][direction] > new_cost
+
+ queue = [(0, 0, -1, 0)]
+ N = len(board)
+ directions = [(0, -1), (-1, 0), (0, 1), (1, 0)]
+ visited = [[[0 for _ in range(4)] for _ in range(N)] for _ in range(N)]
+ answer = float("inf")
+
+ while queue:
+ x, y, prev_direction, cost = queue.pop(0)
+
+ for direction, (dx, dy) in enumerate(directions):
+ new_x, new_y = x + dx, y + dy
+
+ if is_blocked(new_x, new_y):
+ continue
+
+ new_cost = calculate_cost(direction, prev_direction, cost)
+
+ if (new_x, new_y) == (N - 1, N - 1):
+ answer = min(answer, new_cost)
+ elif isShouldUpdate(new_x, new_y, direction, new_cost):
+ queue.append((new_x, new_y, direction, new_cost))
+ visited[new_x][new_y][direction] = new_cost
+
+ return answer
\ No newline at end of file
diff --git a/HHNAM/41to50/46.py b/HHNAM/41to50/46.py
new file mode 100644
index 0000000..adeb4e5
--- /dev/null
+++ b/HHNAM/41to50/46.py
@@ -0,0 +1,27 @@
+def solution(n, wires):
+ graph = [[] for _ in range(n + 1)]
+ for a, b in wires:
+ graph[a].append(b)
+ graph[b].append(a)
+
+ def dfs(node, parent):
+ cnt = 1
+ for child in graph[node]:
+ if child != parent:
+ cnt += dfs(child, node)
+ return cnt
+
+ min_diff = float("inf")
+ for a, b in wires:
+ graph[a].remove(b)
+ graph[b].remove(a)
+
+ cnt_a = dfs(a, b)
+ cnt_b = n - cnt_a
+
+ min_diff = min(min_diff, abs(cnt_a - cnt_b))
+
+ graph[a].append(b)
+ graph[b].append(a)
+
+ return min_diff
\ No newline at end of file
diff --git a/HHNAM/41to50/47.py b/HHNAM/41to50/47.py
new file mode 100644
index 0000000..cbbba82
--- /dev/null
+++ b/HHNAM/41to50/47.py
@@ -0,0 +1,19 @@
+def solution(N):
+ results = []
+
+ def backtrack(sum, selected_nums, start):
+ if sum == 10:
+ results.append(selected_nums)
+ return
+
+ for i in range(start, N + 1):
+ if sum + i <= 10:
+ backtrack(sum + i, selected_nums + [i], i + 1)
+
+ backtrack(0, [], 1)
+ return results
+
+
+# print(solution(5))
+# print(solution(2))
+# print(solution(7))
\ No newline at end of file
diff --git a/HHNAM/41to50/48.py b/HHNAM/41to50/48.py
new file mode 100644
index 0000000..b145e95
--- /dev/null
+++ b/HHNAM/41to50/48.py
@@ -0,0 +1,54 @@
+def solution(board):
+ def is_valid(num, row, col):
+ return not (in_row(num, row) or in_col(num, col) or in_box(num, row, col))
+
+ def in_row(num, row):
+ return num in board[row]
+
+ def in_col(num, col):
+ return num in (board[i][col] for i in range(9))
+
+ def in_box(num, row, col):
+ box_row = (row // 3) * 3
+ box_col = (col // 3) * 3
+ for i in range(box_row, box_row + 3):
+ for j in range(box_col, box_col + 3):
+ if board[i][j] == num:
+ return True
+ return False
+
+ def find_empty_position():
+ for i in range(9):
+ for j in range(9):
+ if board[i][j] == 0:
+ return i, j
+ return None
+
+ def find_solution():
+ empty_pos = find_empty_position()
+ if not empty_pos:
+ return True
+ row, col = empty_pos
+ for num in range(1, 10):
+ if is_valid(num, row, col):
+ board[row][col] = num
+ if find_solution():
+ return True
+ board[row][col] = 0
+ return False
+
+ find_solution()
+ return board
+
+
+'''
+print(solution([[5, 3, 0, 0, 7, 0, 0, 0, 0],
+ [6, 0, 0, 1, 9, 5, 0, 0, 0],
+ [0, 9, 8, 0, 0, 0, 0, 6, 0],
+ [8, 0, 0, 0, 6, 0, 0, 0, 3],
+ [4, 0, 0, 8, 0, 3, 0, 0, 1],
+ [7, 0, 0, 0, 2, 0, 0, 0, 6],
+ [0, 6, 0, 0, 0, 0, 2, 8, 0],
+ [0, 0, 0, 4, 1, 9, 0, 0, 5],
+ [0, 0, 0, 0, 8, 0, 0, 7, 9]]))
+'''
\ No newline at end of file
diff --git a/HHNAM/41to50/49.py b/HHNAM/41to50/49.py
new file mode 100644
index 0000000..5041762
--- /dev/null
+++ b/HHNAM/41to50/49.py
@@ -0,0 +1,15 @@
+def dfs(cur_k, cnt, dungeons, visited):
+ answer_max = cnt
+ for i in range(len(dungeons)):
+ if cur_k >= dungeons[i][0] and visited[i] == 0:
+ visited[i] = 1
+ answer_max = max(
+ answer_max, dfs(cur_k - dungeons[i][1], cnt + 1, dungeons, visited)
+ )
+ visited[i] = 0
+ return answer_max
+
+def solution(k, dungeons):
+ visited = [0] * len(dungeons)
+ answer_max = dfs(k, 0, dungeons, visited)
+ return answer_max
\ No newline at end of file
diff --git a/HHNAM/41to50/50.py b/HHNAM/41to50/50.py
new file mode 100644
index 0000000..4567405
--- /dev/null
+++ b/HHNAM/41to50/50.py
@@ -0,0 +1,16 @@
+def getAns(n, y, width, diagonal1, diagonal2):
+ ans = 0
+ if y == n:
+ ans += 1
+ else:
+ for i in range(n):
+ if width[i] or diagonal1[i + y] or diagonal2[i - y + n]:
+ continue
+ width[i] = diagonal1[i + y] = diagonal2[i - y + n] = True
+ ans += getAns(n, y + 1, width, diagonal1, diagonal2)
+ width[i] = diagonal1[i + y] = diagonal2[i - y + n] = False
+ return ans
+
+def solution(n):
+ ans = getAns(n, 0, [False] * n, [False] * (n * 2), [False] * (n * 2))
+ return ans
\ No newline at end of file
diff --git a/HHNAM/51to60/51.py b/HHNAM/51to60/51.py
new file mode 100644
index 0000000..683cb79
--- /dev/null
+++ b/HHNAM/51to60/51.py
@@ -0,0 +1,34 @@
+from itertools import combinations_with_replacement
+from collections import Counter
+
+def solution(n, info):
+ maxdiff, max_comb = 0, {}
+
+ def calculate_score(combi):
+ score1, score2 = 0, 0
+ for i in range(1, 11):
+ if info[10 - i] < combi.count(i):
+ score1 += i
+ elif info[10 - i] > 0:
+ score2 += i
+ return score1, score2
+
+ def calculate_diff(diff, cnt):
+ nonlocal maxdiff, max_comb
+ if diff > maxdiff:
+ max_comb = cnt
+ maxdiff = diff
+
+ for combi in combinations_with_replacement(range(11), n):
+ cnt = Counter(combi)
+ score1, score2 = calculate_score(combi)
+ diff = score1 - score2
+ calculate_diff(diff, cnt)
+
+ if maxdiff > 0:
+ answer = [0] * 11
+ for n in max_comb:
+ answer[10 - n] = max_comb[n]
+ return answer
+ else:
+ return [-1]
\ No newline at end of file
diff --git a/HHNAM/51to60/52.py b/HHNAM/51to60/52.py
new file mode 100644
index 0000000..5c84cd9
--- /dev/null
+++ b/HHNAM/51to60/52.py
@@ -0,0 +1,22 @@
+from itertools import permutations
+
+def solution(n, weak, dist):
+ length = len(weak)
+ for i in range(length):
+ weak.append(weak[i] + n)
+
+ answer = len(dist) + 1
+
+ for i in range(length):
+ for friends in permutations(dist, len(dist)):
+ cnt = 1
+ position = weak[i] + friends[cnt - 1]
+ for j in range(i, i + length):
+ if position < weak[j]:
+ cnt += 1
+ if cnt > len(dist):
+ break
+ position = weak[j] + friends[cnt - 1]
+ answer = min(answer, cnt)
+
+ return answer if answer <= len(dist) else -1
\ No newline at end of file
diff --git a/HHNAM/51to60/53.py b/HHNAM/51to60/53.py
new file mode 100644
index 0000000..091adaf
--- /dev/null
+++ b/HHNAM/51to60/53.py
@@ -0,0 +1,38 @@
+def solution(board, aloc, bloc):
+ ROW, COL = len(board), len(board[0])
+ DR, DC = [-1, 0, 1, 0], [0, 1, 0, -1]
+
+ def is_valid_pos(r, c):
+ return 0 <= r < ROW and 0 <= c < COL
+
+ def recursive_func(alpha_pos, beta_pos, visited, step):
+ r, c = alpha_pos if step % 2 == 0 else beta_pos
+ can_move = False
+ is_opponent_winner = True
+ win_steps, lose_steps = [], []
+
+ for i in range(4):
+ nr, nc = r + DR[i], c + DC[i]
+ if is_valid_pos(nr, nc) and (nr, nc) not in visited and board[nr][nc]:
+ can_move = True
+ if alpha_pos == beta_pos:
+ return True, step + 1
+
+ win, steps_left = (
+ recursive_func([nr, nc], beta_pos, visited | {(r, c)}, step + 1)
+ if step % 2 == 0
+ else recursive_func(
+ alpha_pos, [nr, nc], visited | {(r, c)}, step + 1
+ )
+ )
+ is_opponent_winner &= win
+ (win_steps if win else lose_steps).append(steps_left)
+
+ if not can_move:
+ return False, step
+ if is_opponent_winner:
+ return False, max(win_steps)
+ return True, min(lose_steps)
+
+ _, steps = recursive_func(aloc, bloc, set(), 0)
+ return steps
\ No newline at end of file
diff --git a/HHNAM/51to60/54.py b/HHNAM/51to60/54.py
new file mode 100644
index 0000000..d7cd536
--- /dev/null
+++ b/HHNAM/51to60/54.py
@@ -0,0 +1,15 @@
+def solution(s):
+ counts = [0] * 26
+
+ for c in s:
+ counts[ord(c) - ord("a")] += 1
+
+ sorted_str = ""
+ for i in range(26):
+ sorted_str += chr(i + ord("a")) * counts[i]
+
+ return sorted_str
+
+
+# print(solution('hello'))
+# print(solution('algorithm'))
\ No newline at end of file
diff --git a/HHNAM/51to60/55.py b/HHNAM/51to60/55.py
new file mode 100644
index 0000000..362287a
--- /dev/null
+++ b/HHNAM/51to60/55.py
@@ -0,0 +1,24 @@
+def solution(arr1, arr2):
+ merged = []
+ i, j = 0, 0
+
+ while i < len(arr1) and j < len(arr2):
+ if arr1[i] <= arr2[j]:
+ merged.append(arr1[i])
+ i += 1
+ else:
+ merged.append(arr2[j])
+ j += 1
+
+ while i < len(arr1):
+ merged.append(arr1[i])
+ i += 1
+ while j < len(arr2):
+ merged.append(arr2[j])
+ j += 1
+
+ return merged
+
+
+# print(solution([1, 3, 5], [2, 4, 6]))
+# print(solution([1, 2, 3], [4, 5, 6]))
\ No newline at end of file
diff --git a/HHNAM/51to60/56.py b/HHNAM/51to60/56.py
new file mode 100644
index 0000000..f890c50
--- /dev/null
+++ b/HHNAM/51to60/56.py
@@ -0,0 +1,2 @@
+def solution(strings, n):
+ return sorted(strings, key=lambda x: (x[n], x))
\ No newline at end of file
diff --git a/HHNAM/51to60/57.py b/HHNAM/51to60/57.py
new file mode 100644
index 0000000..6ff3808
--- /dev/null
+++ b/HHNAM/51to60/57.py
@@ -0,0 +1,5 @@
+def solution(n):
+ digits = list(str(n))
+ digits.sort(reverse=True)
+ answer = int("".join(digits))
+ return answer
\ No newline at end of file
diff --git a/HHNAM/51to60/58.py b/HHNAM/51to60/58.py
new file mode 100644
index 0000000..b9b787a
--- /dev/null
+++ b/HHNAM/51to60/58.py
@@ -0,0 +1,8 @@
+def solution(array, commands):
+ answer = []
+ for cmd in commands:
+ i, j, k = cmd
+ sliced_arr = array[i - 1 : j]
+ sorted_arr = sorted(sliced_arr)
+ answer.append(sorted_arr[k - 1])
+ return answer
\ No newline at end of file
diff --git a/HHNAM/51to60/59.py b/HHNAM/51to60/59.py
new file mode 100644
index 0000000..b750057
--- /dev/null
+++ b/HHNAM/51to60/59.py
@@ -0,0 +1,11 @@
+import functools
+
+def compare(a, b):
+ t1 = str(a) + str(b)
+ t2 = str(b) + str(a)
+ return (int(t1) > int(t2)) - (int(t1) < int(t2))
+
+def solution(numbers):
+ sorted_nums = sorted(numbers, key=functools.cmp_to_key(compare), reverse=True)
+ answer = "".join(str(x) for x in sorted_nums)
+ return "0" if int(answer) == 0 else answer
\ No newline at end of file
diff --git a/HHNAM/51to60/60.py b/HHNAM/51to60/60.py
new file mode 100644
index 0000000..d84e77e
--- /dev/null
+++ b/HHNAM/51to60/60.py
@@ -0,0 +1,11 @@
+def solution(s):
+ s = s[2:-2].split("}, {")
+ s = sorted(s, key=len)
+ answer = []
+ for element in s:
+ numbers = element.split(",")
+ for number in numbers:
+ if int(number) not in answer:
+ answer.append(int(number))
+
+ return answer
\ No newline at end of file
diff --git a/MSKIM/31to40/31.py b/MSKIM/31to40/31.py
new file mode 100644
index 0000000..d15f9bf
--- /dev/null
+++ b/MSKIM/31to40/31.py
@@ -0,0 +1,12 @@
+from collections import Counter
+
+n = int(input())
+n_list = list(map(int, input().split()))
+m = int(input())
+m_list = list(map(int, input().split()))
+
+counter = Counter(n_list)
+
+answer = [counter[i] for i in m_list]
+
+print(" ".join(map(str, answer)))
diff --git a/MSKIM/31to40/38.py b/MSKIM/31to40/38.py
new file mode 100644
index 0000000..984a418
--- /dev/null
+++ b/MSKIM/31to40/38.py
@@ -0,0 +1,30 @@
+#난 dic쓸거임
+
+def solution(graph, start):
+ adj_list = {}
+
+ for u, v in graph:
+ if u in adj_list:
+ adj_list[u].append(v)
+ else:
+ adj_list[u] = [v]
+
+
+ def dfs(node, visited, result):
+ visited.add(node)
+ result.append(node)
+
+ if node in adj_list:
+ for neighbor in adj_list[node]:
+ if neighbor not in visited:
+ dfs(neighbor, visited, result)
+
+ visited = set()
+ result = []
+ dfs(start, visited, result)
+ return result
+
+graph = [['A', 'B'], ['A', 'C'], ['B', 'D'], ['B', 'E'], ['C', 'F'], ['E', 'F']]
+start_node = 'A'
+
+print(solution(graph, start_node))
diff --git a/MSKIM/31to40/39.py b/MSKIM/31to40/39.py
new file mode 100644
index 0000000..d363ac3
--- /dev/null
+++ b/MSKIM/31to40/39.py
@@ -0,0 +1,35 @@
+from collections import deque
+
+def solution(graph, start):
+ adj_list = {} #
+ for u, v in graph:
+ if u in adj_list:
+ adj_list[u].append(v)
+ else:
+ adj_list[u] = [v]
+
+
+ def bfs(start):
+ visited = set()
+ queue = deque([start])
+ visited.add(start)
+ result = [start]
+
+ while queue:
+ node = queue.popleft()
+ if node in adj_list:
+ for neighbor in adj_list[node]:
+ if neighbor not in visited:
+ queue.append(neighbor)
+ visited.add(neighbor)
+ result.append(neighbor)
+
+ return result
+
+ return bfs(start)
+
+
+graph = [['A', 'B'], ['A', 'C'], ['B', 'D'], ['B', 'E'], ['C', 'F'], ['E', 'F']]
+start_node = 'A'
+
+print(solution(graph, start_node))
diff --git a/MSKIM/31to40/40.py b/MSKIM/31to40/40.py
new file mode 100644
index 0000000..fe90eea
--- /dev/null
+++ b/MSKIM/31to40/40.py
@@ -0,0 +1,38 @@
+import heapq
+
+def solution(graph, start):
+ distances = {node: float("inf") for node in graph}
+ distances[start] = 0
+ queue = []
+
+ heapq.heappush(queue, [distances[start], start])
+ paths = {start: [start]}
+
+ while queue:
+ current_distance, current_node = heapq.heappop(queue)
+
+ if distances[current_node] < current_distance:
+ continue
+
+ for adjacent_node, weight in graph[current_node].items():
+ distance = current_distance + weight
+
+ if distance < distances[adjacent_node]:
+ distances[adjacent_node] = distance
+ paths[adjacent_node] = paths[current_node] + [adjacent_node]
+
+ heapq.heappush(queue, [distance, adjacent_node])
+
+ sorted_paths = {node: paths[node] for node in sorted(paths)}
+ return [distances, sorted_paths]
+
+
+graph = {
+ 'A': {'B': 1, 'C': 4},
+ 'B': {'A': 1, 'C': 2, 'D': 5},
+ 'C': {'A': 4, 'B': 2, 'D': 1},
+ 'D': {'B': 5, 'C': 1}
+}
+start_node = 'A'
+
+print(solution(graph, start_node))
diff --git a/README.md b/README.md
index ebf11ce..86e0530 100644
--- a/README.md
+++ b/README.md
@@ -23,25 +23,25 @@
| Python : 28 Java : 14 C : 0 C++ : 0 C# : 0 |
| 김민승 |
- 27 |
- 27 |
- 73 |
- -73000 |
- Python : 27 Java : 0 C : 0 C++ : 0 C# : 0 |
+ 31 |
+ 31 |
+ 69 |
+ -69000 |
+ Python : 31 Java : 0 C : 0 C++ : 0 C# : 0 |
| 남현호 |
- 4 |
- 4 |
- 96 |
- -96000 |
- Python : 4 Java : 0 C : 0 C++ : 0 C# : 0 |
+ 60 |
+ 60 |
+ 40 |
+ -40000 |
+ Python : 60 Java : 0 C : 0 C++ : 0 C# : 0 |
| 류정민 |
- 10 |
- 10 |
- 90 |
- -90000 |
- Python : 10 Java : 0 C : 0 C++ : 0 C# : 0 |
+ 12 |
+ 12 |
+ 88 |
+ -88000 |
+ Python : 12 Java : 0 C : 0 C++ : 0 C# : 0 |
| 이창석 |
5 |
@@ -51,14 +51,14 @@
Python : 5 Java : 0 C : 0 C++ : 0 C# : 0 |
| 최수연 |
- 22 |
- 24 |
- 78 |
- -78000 |
- Python : 24 Java : 0 C : 0 C++ : 0 C# : 0 |
+ 33 |
+ 35 |
+ 67 |
+ -67000 |
+ Python : 35 Java : 0 C : 0 C++ : 0 C# : 0 |
-총 Push 횟수 : 120회
+총 Push 횟수 : 145회
# 업로드 방법
### 1. 파일명
diff --git a/SYCHOI/11to20/19.py b/SYCHOI/11to20/19.py
new file mode 100644
index 0000000..92731e8
--- /dev/null
+++ b/SYCHOI/11to20/19.py
@@ -0,0 +1,25 @@
+def polynomial_hash(str) :
+ p = 31
+ m = 1000000007
+ hash_value = 0
+
+ for char in str :
+ hash_value = (hash_value * p + ord(char)) % m # why???
+ return hash_value
+
+def solution(string_list, query_list) :
+ # string_list에 있는 문자열들을 해싱해서 hash_list에 저장
+ hash_list = [polynomial_hash(str) for str in string_list]
+
+ result = []
+ for query in query_list :
+ query_hash = polynomial_hash(query) # query_list에 있는 문자열(query)들을 해싱해서 query_hash에 저장
+ if query_hash in hash_list :
+ result.append(True) # 해당 해싱값이 hash_list에 있으면 True 저장
+ else :
+ result.append(False) # 해당 해싱값이 hash_list에 없으면 False 저장
+ return result
+
+
+#TEST 코드입니다. 주석을 풀어서 확인해보세요
+print(solution(["apple", "banana", "cherry"], ["banana", "kiwi", "melon", "apple"]))
\ No newline at end of file
diff --git a/SYCHOI/21to30/21.py b/SYCHOI/21to30/21.py
new file mode 100644
index 0000000..6fd2d7c
--- /dev/null
+++ b/SYCHOI/21to30/21.py
@@ -0,0 +1,30 @@
+def solution(want, number, discount) :
+ dic = {}
+
+ # 정현이가 원하는 제품과 개수를 dictionary에 저장
+ for i in range(len(want)) :
+ dic[want[i]] = number[i]
+
+ # 할인 상품과 원하는 제품 비교
+ cnt = 0 # 원하는 제품을 모두 할인받을 수 있는 회원 등록 날짜 수
+ for j in range(len(discount) - 9) : # 10일 순회할 수 있을 만큼만 discount 순회
+ tenDays = {}
+
+ for k in range(j, j + 10) : # 특정 날짜(k)부터 10일간 discount 물품 순회
+ if discount[k] in dic : # 할인 품목이 정현이가 원하는 제품 목록에 있으면
+ tenDays[discount[k]] = tenDays.get(discount[k], 0) + 1 # 10일동안 할인받는 물품들의 개수를 tenDays 딕셔너리에 저장
+ # tenDays에 이미 있으면 해당 값(value) + 1, 없으면 기본값(default value) + 1
+ if tenDays == dic :
+ cnt += 1 # 10일 연속으로 원하는 제품을 개수만큼 할인받을 수 있다면 cnt++
+ break # 책과 다름. 조금 수정함..
+
+
+ return cnt
+
+
+
+
+
+#TEST 코드입니다. 주석을 풀어서 확인해보세요
+print(solution(["banana", "apple", "rice", "pork", "pot"], [3, 2, 2, 2, 1], ["chicken", "apple", "apple", "banana", "rice", "apple", "pork", "banana", "pork", "rice", "pot", "banana", "apple", "banana"]))
+print(solution(["apple"], [10], ["banana", "banana", "banana", "banana", "banana", "banana", "banana", "banana", "banana", "banana"]))
\ No newline at end of file
diff --git a/SYCHOI/21to30/27.py b/SYCHOI/21to30/27.py
new file mode 100644
index 0000000..343cb31
--- /dev/null
+++ b/SYCHOI/21to30/27.py
@@ -0,0 +1,60 @@
+# 포인터 Node 만드는 방법(class Node)와 이진탐색트리 만드는 방법(class BST)는 반드시 익혀두기!!
+
+class Node : # 포인터로 트리 표현하기
+ def __init__(self, key) : # 클래스의 첫 def(__init__)의 첫번째 인수는 무조건 self임. 호출 시 사용x
+ self.left = None # 왼쪽 자식 노드
+ self.right = None # 오른쪽 자식 노드
+ self.val = key # 현재 노드의 값
+
+class BST : # Binary Search Tree
+ def __init__(self) :
+ self.root = None
+
+ # Binary Search Tree(이진탐색트리) 만드는 함수
+ def insert(self, key) : # key == 추가하려고 하는 값
+ if not self.root : # self.root가 없으면
+ self.root = Node(key) # 'Node' 클래스를 통해 self.root 선언
+ else : # self.root가 있으면
+ curr = self.root # curr에 self.root 값 저장
+ while True :
+ if key < curr.val : # key 값이 BST의 현재 값보다 작으면
+ if curr.left :
+ curr = curr.left # 왼쪽 노드가 있으면 현재 값 = 왼쪽 노드 값
+ else :
+ curr.left = Node(key) # 왼쪽 노드가 없으면 왼쪽 노드에 현재 값 넣은 노드 생성(break)
+ break
+ else : # key 값이 BST의 현재 값보다 크면
+ if curr.right :
+ curr = curr.right # 오른쪽 노드가 있으면 현재 값 = 오른쪽 노드 값
+ else :
+ curr.right = Node(key) # 오른쪽 노드가 없으면 오른쪽 노드에 현재 값 넣은 노드 생성(break)
+ break
+
+ # Binary Search Tree(이진탐색트리) 탐색하는 함수
+ def search(self, key) : # key == 찾으려고 하는 값
+ curr = self.root # 트리의 루트 값을 기본 값으로 설정
+ while curr and curr.val != key : # 현재 값(루트 값)이 key(찾는 값)가 아니면 실행
+ if key < curr.val :
+ curr = curr.left # 찾는 값이 현재 값보다 작으면 왼쪽 노드로 이동
+ else :
+ curr = curr.right # 찾는 값이 현재 값보다 크면 오른쪽 노드로 이동
+ return curr # while문을 벗어나면(현재 값 == 찾는 값) 현재 값 리턴
+
+def solution(lst, search_lst) :
+ idx = BST() # idx에 BST 클래스 입력
+ for n in lst :
+ idx.insert(n) # lst에 있는 값들을 순서대로 idx 클래스의 insert 함수로 추가
+
+ result = []
+ for m in search_lst :
+ if idx.search(m) :
+ result.append(True)
+ else :
+ result.append(False)
+
+ return result
+
+
+#TEST 코드입니다. 주석을 풀어서 확인해보세요
+print(solution([5, 3, 8, 4, 2, 1, 7, 10], [1, 2, 5, 6]))
+print(solution([1, 3, 5, 7, 9], [2, 4, 6, 8, 10]))
\ No newline at end of file
diff --git a/SYCHOI/21to30/28.py b/SYCHOI/21to30/28.py
new file mode 100644
index 0000000..87aafdc
--- /dev/null
+++ b/SYCHOI/21to30/28.py
@@ -0,0 +1,14 @@
+def solution(N, A, B) :
+ result = 1
+ while (1) :
+ A = int((A + 1) / 2) # A = (A + 1) // 2
+ B = int((B + 1) / 2) # B = (B + 1) // 2
+ if A == B :
+ break
+ result += 1
+
+ return result
+
+
+#TEST 코드입니다. 주석을 풀어서 확인해보세요
+print(solution(8, 4, 7))
\ No newline at end of file
diff --git a/SYCHOI/21to30/29.py b/SYCHOI/21to30/29.py
new file mode 100644
index 0000000..d1a294a
--- /dev/null
+++ b/SYCHOI/21to30/29.py
@@ -0,0 +1,37 @@
+import math
+
+def solution(enroll, referral, seller, amount) :
+ dict = {}
+ earn = {}
+ for i in range(len(enroll)) :
+ dict[enroll[i]] = referral[i]
+ earn[enroll[i]] = 0
+
+ for i in range(len(seller)) :
+ name = seller[i]
+ money = amount[i] * 100 # 칫솔 개당 100원
+
+ while name != "-" :
+ if earn[name] == 0 :
+ earn[name] = money * 0.9
+ else :
+ earn[name] += money * 0.9
+ money = money * 0.1 # referral이 enroll한테 넘겨받은 돈(10%)
+ if money < 1 :
+ earn[name] += money # 10%를 계산한 금액이 1원 미만이면 이득을 분배하지 않고 자신이 모두 가짐
+ name = dict[name] # referral을 name에 초기화
+
+ result = []
+ for value in earn.values() :
+ result.append(round(value))
+ return result
+
+
+
+
+
+
+
+#TEST 코드입니다. 주석을 풀어서 확인해보세요
+print(solution(["john", "mary", "edward", "sam", "emily", "jaimie", "tod", "young"], ["-", "-", "mary", "edward", "mary", "mary", "jaimie", "edward"], ["young", "john", "tod", "emily", "mary"], [12, 4, 2, 5, 10]))
+print(solution(["john", "mary", "edward", "sam", "emily", "jaimie", "tod", "young"], ["-", "-", "mary", "edward", "mary", "mary", "jaimie", "edward"], ["sam", "emily", "jaimie", "edward"], [2, 3, 5, 4]))
\ No newline at end of file
diff --git a/SYCHOI/21to30/30.py b/SYCHOI/21to30/30.py
new file mode 100644
index 0000000..9e155a8
--- /dev/null
+++ b/SYCHOI/21to30/30.py
@@ -0,0 +1,55 @@
+from collections import deque
+
+def isValid(ny, nx, n, m, maps) :
+ return 0 <= ny < n and 0 <= nx < m and maps[ny][nx] != "X"
+ # 0 <= ny < n : 방문할 y좌표가 지도 내에 있고 / 0 <= nx < m : 방문할 x좌표가 지도 내에 있고
+ # 방문할 좌표가 벽이 아니면 return
+
+def append_to_Queue(ny, nx, k, time, visited, q) :
+ if not visited[ny][nx][k] : # 방문하지 않았다면
+ visited[ny][nx][k] = True # 방문 표시
+ q.append((ny, nx, k, time + 1)) # time + 1 상태 q에 append
+
+def solution(maps) :
+ n, m = len(maps), len(maps[0]) # n : maps의 행 개수, m : maps의 열 개수
+ visited = [[[False for _ in range(2)] for _ in range(m)] for _ in range(n)] # [False, False]를 m개의 열 개수만큼, n개의 행 개수만큼 생성
+ # False for _ in range(2) : [False, False] 생성
+
+ # dy, dx의 인덱스에 따라 상/하/좌/우 구별 가능 : dx[0] & dy[0] = 위로 이동
+ dy = [-1, 1, 0, 0]; dx = [0, 0, -1, 1]
+ endY, endX = -1, -1 # 도착점의 x, y 좌표 넣는 변수. -1로 초기화한다
+ q = deque() # q라는 변수에 덱 기능 선언
+
+ for i in range(n) :
+ for j in range(m) :
+ if maps[i][j] == "S" :
+ q.append((i, j, 0, 0)) # 덱 q에 시작점 좌표 입력 (q의 오른쪽 끝에 삽입)
+ visited[i][j][0] = True # (i, j) 좌표 방문 표시
+ if maps[i][j] == "E" :
+ endY, endX = i, j # (i, j) 출구 좌표 입력
+
+ while q :
+ y, x, k, time = q.popleft() # (q의 왼쪽 끝 원소 pop)
+ # y좌표 , x좌표, 레버 동작 여부, 시작 지점부터 해당 좌표까지 가는 데 걸린 시간
+
+ if y== endY and x == endX and k == 1 : # 왜 k == 1이어야 할까..?
+ return time
+
+ for i in range(4) : # 현재 좌표(y, x)에서 상하좌우 1칸씩 이동
+ ny, nx = y + dy[i], x + dx[i] # 이동한 좌표 ny, nx에 저장
+
+ if not isValid(ny, nx, n, m, maps) :
+ continue # 이동 불가한 위치라면 continue
+
+ if maps[ny][nx] == "L" :
+ append_to_Queue(ny, nx, 1, time, visited, q) # 이동한 곳이 레버라면 k = 1 적용
+ else :
+ append_to_Queue(ny, nx, k, time, visited, q) # 이동한 곳이 레버가 아니라면 k = 0(그대로)
+
+ return -1
+
+
+
+#TEST 코드입니다. 주석을 풀어서 확인해보세요
+print(solution(["SOOOL", "XXXXO", "OOOOO", "OXXXX", "OOOOE"]))
+print(solution(["LOOXS", "OOOOX", "OOOOO", "OOOOO", "EOOOO"]))
\ No newline at end of file
diff --git a/SYCHOI/31to40/32.py b/SYCHOI/31to40/32.py
new file mode 100644
index 0000000..0d65292
--- /dev/null
+++ b/SYCHOI/31to40/32.py
@@ -0,0 +1,88 @@
+from collections import deque
+
+class Node :
+ def __init__(self, info, num, left=None, right=None) :
+ self.info = info # 노드의 좌표 정보
+ self.left = left # 노드의 왼쪽 자식 노드
+ self.right = right # 노드의 오른쪽 자식 노드
+ self.num = num # 노드의 번호
+
+ def has_left(self) :
+ return self.left is not None # 왼쪽 노드에 값이 있으면 리턴
+
+ def has_right(self) :
+ return self.right is not None # 오른쪽 노드에 값이 없으면 리턴
+
+
+def make_BT(nodeinfo) :
+ # 노드의 개수만큼 1부터 노드길이 + 1까지의 리스트 생성
+ nodes = [i for i in range(1, len(nodeinfo) + 1)]
+
+ # y좌표 내림차순 정렬, y좌표가 같을 때 x좌표 오름차순 정렬 (y축은 크고 x축은 작은 노드의 인덱스값 정렬)
+ # nodes의 원소는 1부터, nodesinfo의 원소는 0부터 시작하므로 nodeinfo의 1차원 리스트에 대해서 x - 1 적용
+ nodes.sort(key = lambda x : (nodeinfo[x - 1][1], -nodeinfo[x - 1][0]), reverse=True)
+ root = None # 루트 노드 초기화(None으로)
+
+ # root를 기준으로 순회해서 트리에 노드 추가
+ for i in range(len(nodes)) :
+ if root is None :
+ root = Node(nodeinfo[nodes[0] - 1], nodes[0]) # 'root' 노드의 info = nodeinfo[nodes[0] - 1], num = nodes[0]
+ else :
+ parent = root
+ node = Node(nodeinfo[nodes[i] - 1], nodes[i]) # 자식 노드들의 info = nodeinfo[nodes[i] - 1], num = nodes[i]
+
+ while True :
+ # info[0] : 해당 노드(node, parent)의 x좌표
+ if node.info[0] < parent.info[0] : # parent의 x좌표가 node보다 크면
+ if parent.has_left() :
+ parent = parent.left # parent의 왼쪽 노드에 값이 있으면 현재 parent를 parent의 왼쪽 노드로
+ continue
+ parent.left = node # parent의 왼쪽 노드에 값이 없으면 node 삽입
+ break
+ else : # node의 x좌표가 parent보다 크면
+ if parent.has_right() :
+ parent = parent.right # parent의 오른쪽 노드에 값이 있으면 현재 parent를 parent의 오른쪽 노드로
+ continue
+ parent.right = node # parent의 오른쪽 노드에 값이 없으면 node 삽입
+ break
+ return root
+
+
+def pre_order(root, answer) : # 생성한 이진트리의 root, 전위순회를 담을 answer 리스트(answer[0])
+ stack = [root] # stack에 root 노드 삽입
+ while stack :
+ node = stack.pop() # stack의 최상단 노드 방문
+ if node is None :
+ continue # 부모 노드의 왼쪽or오른쪽 노드가 없을 경우
+ answer[0].append(node.num) # 방문한 노드의 값 answer[0]에 append
+ stack.append(node.right)
+ stack.append(node.left) # stack은 LIFO이기 때문에 먼저 방문할 왼쪽 노드를 나중에 삽입
+
+
+def post_order(root, answer) : # 생성한 이진트리의 root, 후위순회를 담을 answer 리스트(answer[1])
+ stack = [(root, False)] # stack에 root 노드 & 방문 여부 삽입
+ while stack :
+ node, visited = stack.pop() # stack의 최상단 노드 방문
+ if node is None :
+ continue # 부모 노드의 왼쪽or오른쪽 노드가 없을 경우
+ if visited :
+ answer[1].append(node.num) # 방문
+ else :
+ stack.append((node, True))
+ stack.append((node.right, False))
+ stack.append((node.left, False))
+
+
+
+
+def solution(nodeinfo) :
+ answer = [[], []] # 이진 트리의 각각 [전위 순회], [후위 순회] 결과를 담을 변수
+ root = make_BT(nodeinfo) # 입력받은 노드의 좌표(nodeinfo)를 통해 이진 트리 생성
+ pre_order(root, answer)
+ post_order(root, answer)
+
+ return answer
+
+
+#TEST 코드입니다. 주석을 풀어서 확인해보세요
+print(solution([[5, 3], [11, 5], [13, 3], [3, 5], [6, 1], [1, 3], [8, 6], [7, 2], [2, 2]]))
\ No newline at end of file
diff --git a/SYCHOI/31to40/33.py b/SYCHOI/31to40/33.py
new file mode 100644
index 0000000..f563347
--- /dev/null
+++ b/SYCHOI/31to40/33.py
@@ -0,0 +1,35 @@
+# 리스트 형식의 result를 전역변수로 생성했었음. 하지만 파이썬에서는 전역변수를 사용할 때 매 함수마다 'global 전역변수명' 형식으로 호출해줘야 하기 때문에 번거로움. 그냥 함수의 매개변수로 호출
+
+def find(result, x) : # x가 속한 집합의 대표 원소(Root) 찾기
+ if result[x] == x :
+ return result[x] # 인덱스 값 == 노드 값 : 부모 노드(Root)
+
+ parent = find(result, result[x]) # 인덱스 값 != 노드 값 : 자식 노드 => 부모노드 찾기(재귀함수)
+ return parent
+
+def union(result, x, y) : # x와 y가 속한 두 집합 합치기
+ root1 = find(result, x)
+ root2 = find(result, y) # 각 노드(x, y)가 속한 집합의 루트 노드 찾기
+
+ result[root2] = root1 # y가 속한 집합의 루트노드(root2)를 x가 속한 집합의 루트노드(root1)와 합치기
+
+
+def solution(k, operations) :
+ # 노드의 값 : 인덱스 , 부모노드 : 리스트 값
+ result = list(range(k)) # 처음에는 각 노드가 자기 자신을 부모로 가지도록 초기화
+ n = k
+
+ for lst in operations :
+ if lst[0] == 'u' :
+ union(result, lst[1], lst[2])
+ # print(lst[0], lst[1], lst[2])
+ # elif lst[0] == 'f' :
+ # root = find(lst[1])
+ # print(lst[0], lst[1])
+
+ n = len(set(find(result, i) for i in range(k)))
+ return n
+
+#TEST 코드입니다. 주석을 풀어서 확인해보세요
+# print(solution(3, [['u', 0, 1], ['u', 1, 2], ['f', 2]]))
+# print(solution(4, [['u', 0, 1], ['u', 2, 3], ['f', 0]]))
\ No newline at end of file
diff --git a/SYCHOI/31to40/34.py b/SYCHOI/31to40/34.py
new file mode 100644
index 0000000..93c9816
--- /dev/null
+++ b/SYCHOI/31to40/34.py
@@ -0,0 +1,26 @@
+def solution(nums) : # nums : 폰켓몬의 종류 번호가 담긴 1차원 배열
+ halfN = len(nums) // 2 # int(len(nums) / 2)
+ idx = [0 for i in range(max(nums) + 1)]
+
+ cnt = 0
+ for n in nums :
+ if idx[n] == 0 :
+ cnt += 1
+ idx[n] = 1
+
+ if halfN == cnt :
+ return halfN
+
+ # 책의 예시(더 쉬운 방법)
+ # num_set = set(nums) # 폰켓몬 종류의 번호를 중복이 없는 집합으로 생성
+ # n = len(nums)
+ # k = n // 2 # k는 최대 뽑을 수 있는 폰켓몬의 수
+ # return min(k, len(num_set)) # 폰켓몬 종류 수(num_set)와 뽑을 수 있는 폰켓몬의 수(k) 중에 작은 값을 리턴
+
+ return cnt
+
+
+#TEST 코드입니다. 주석을 풀어서 확인해보세요
+# print(solution([3, 1, 2, 3]))
+# print(solution([3, 3, 3, 2, 2, 4]))
+# print(solution([3, 3, 3, 2, 2, 2]))
\ No newline at end of file
diff --git a/SYCHOI/31to40/35.py b/SYCHOI/31to40/35.py
new file mode 100644
index 0000000..20ebb4e
--- /dev/null
+++ b/SYCHOI/31to40/35.py
@@ -0,0 +1,31 @@
+def solution(n, words) :
+ result = []
+ listUp = []
+ idx = 1; round = 1; first = 1
+
+ for word in words :
+ if word in listUp :
+ return [idx, round] # 이미 나온 단어(listUp)가 나오면 리턴
+
+ if first == 0 and word[0] != last :
+ return [idx, round] # (첫단어 제외) 이전 단어의 마지막 알파벳과 현재 단어의 첫 알파벳이 다르면 리턴
+
+ if idx == n :
+ idx = 1
+ round += 1
+ else :
+ idx += 1
+
+ first = 0
+ last = word[-1]
+ listUp.append(word)
+
+ # words 리스트를 무사히 순회하면 [0, 0] 리턴
+ return [0, 0]
+
+
+
+#TEST 코드입니다. 주석을 풀어서 확인해보세요
+# print(solution(3, ["tank", "kick", "know", "wheel", "land", "dream", "mother", "robot", "tank"]))
+# print(solution(5, ["hello", "observe", "effect", "take", "either", "recognize", "encourage", "ensure", "establish", "hang", "gather", "refer", "reference", "estimate", "executive"]))
+# print(solution(2, ["hello", "one", "even", "never", "now", "world", "draw"]))
\ No newline at end of file
diff --git a/SYCHOI/31to40/36.py b/SYCHOI/31to40/36.py
new file mode 100644
index 0000000..57f8ed3
--- /dev/null
+++ b/SYCHOI/31to40/36.py
@@ -0,0 +1,15 @@
+def solution(phone_book) :
+ # 접두어가 겹치는지 쉽게 확인하는 방법 : 정렬
+ phone_book.sort()
+
+ for i in range(len(phone_book)-1) : # 두 개를 비교할 것이기 때문에 phone_book -1까지 비교
+ if phone_book[i + 1].startswith(phone_book[i]) : # startswith() : 앞의 변수가 매개변수로 시작하는지 분별
+ return False # 어떤 번호가 다른 번호의 접두어이면 False
+
+ return True # 그렇지 않으면 True
+
+
+#TEST 코드입니다. 주석을 풀어서 확인해보세요
+# print(solution(["119", "97674223", "1195524421"]))
+# print(solution(["123", "456", "789"]))
+# print(solution(["12", "123", "1235", "567", "88"]))
\ No newline at end of file
diff --git a/total_push_cnt.txt b/total_push_cnt.txt
index 52bd8e4..13c09a0 100644
--- a/total_push_cnt.txt
+++ b/total_push_cnt.txt
@@ -1 +1 @@
-120
+145