1110 added.

1110-Delete-Nodes-And-Return-Forest/cpp-1110/CMakeLists.txt

@@ -0,0 +1,6 @@
+cmake_minimum_required(VERSION 3.14)
+project(C)
+
+set(CMAKE_CXX_STANDARD 14)
+
+add_executable(C main2.cpp)

1110-Delete-Nodes-And-Return-Forest/cpp-1110/main.cpp

@@ -0,0 +1,88 @@
+/// Source : https://leetcode.com/problems/delete-nodes-and-return-forest/
+/// Author : liuyubobobo
+/// Time   : 2019-07-06
+
+#include <iostream>
+#include <vector>
+
+using namespace std;
+
+
+/// Simulations
+/// Time Complexity: O(|to_delete| * n)
+/// Space Complexity: O(h)
+
+/// Definition for a binary tree node.
+struct TreeNode {
+    int val;
+    TreeNode *left;
+    TreeNode *right;
+    TreeNode(int x) : val(x), left(NULL), right(NULL) {}
+};
+
+class Solution {
+public:
+    vector<TreeNode*> delNodes(TreeNode* root, vector<int>& to_delete) {
+
+        vector<TreeNode*> res = {root};
+        for(int e: to_delete)
+            res = delNodes(res, e);
+        return res;
+    }
+
+private:
+    vector<TreeNode*> delNodes(vector<TreeNode*> v, int to_delete){
+
+        vector<TreeNode*> ret;
+        bool ok = false;
+        for(TreeNode* root: v)
+            if(ok || !delNode(root, NULL, -1, root, to_delete, ret))
+                ret.push_back(root);
+            else
+                ok = true;
+
+        return ret;
+    }
+
+    bool delNode(TreeNode* root, TreeNode* parent, int index, TreeNode* node, int to_delete,
+                 vector<TreeNode*>& ret){
+
+        if(!node) return false;
+        if(node->val == to_delete){
+            if(node == root){
+                if(node->left) ret.push_back(node->left);
+                if(node->right) ret.push_back(node->right);
+            }
+            else{
+                if(index == 0) parent->left = NULL;
+                else parent->right = NULL;
+
+                ret.push_back(root);
+                if(node->left) ret.push_back(node->left);
+                if(node->right) ret.push_back(node->right);
+            }
+            return true;
+        }
+
+        if(delNode(root, node, 0, node->left, to_delete, ret))
+            return true;
+        return delNode(root, node, 1, node->right, to_delete, ret);
+    }
+};
+
+
+int main() {
+
+    TreeNode* root = new TreeNode(1);
+    root->left = new TreeNode(2);
+    root->right = new TreeNode(3);
+    root->left->left = new TreeNode(4);
+    root->left->right = new TreeNode(5);
+    root->right->left = new TreeNode(6);
+    root->right->right = new TreeNode(7);
+
+    vector<int> to_delete = {3, 5};
+    Solution().delNodes(root, to_delete);
+
+    return 0;
+}

1110-Delete-Nodes-And-Return-Forest/cpp-1110/main2.cpp

@@ -0,0 +1,63 @@
+/// Source : https://leetcode.com/problems/delete-nodes-and-return-forest/
+/// Author : liuyubobobo
+/// Time   : 2019-07-07
+
+#include <iostream>
+#include <vector>
+#include <unordered_set>
+
+using namespace std;
+
+
+/// Recursion
+/// Time Complexity: O(n)
+/// Space Complexity: O(h)
+
+/// Definition for a binary tree node.
+struct TreeNode {
+    int val;
+    TreeNode *left;
+    TreeNode *right;
+    TreeNode(int x) : val(x), left(NULL), right(NULL) {}
+};
+
+class Solution {
+public:
+    vector<TreeNode*> delNodes(TreeNode* root, vector<int>& to_delete) {
+
+        unordered_set<int> remove_set(to_delete.begin(), to_delete.end());
+        vector<TreeNode*> res;
+        remove(root, true, remove_set, res);
+        return res;
+    }
+
+private:
+    TreeNode* remove(TreeNode* node, bool is_root,
+             const unordered_set<int>& remove_set, vector<TreeNode*>& res){
+
+        if(!node) return NULL;
+
+        bool deleted = remove_set.count(node->val);
+        if(is_root && !deleted) res.push_back(node);
+        node->left = remove(node->left, deleted, remove_set, res);
+        node->right = remove(node->right, deleted, remove_set, res);
+        return deleted ? NULL : node;
+    }
+};
+
+
+int main() {
+
+    TreeNode* root = new TreeNode(1);
+    root->left = new TreeNode(2);
+    root->right = new TreeNode(3);
+    root->left->left = new TreeNode(4);
+    root->left->right = new TreeNode(5);
+    root->right->left = new TreeNode(6);
+    root->right->right = new TreeNode(7);
+
+    vector<int> to_delete = {3, 5};
+    Solution().delNodes(root, to_delete);
+
+    return 0;
+}

readme.md

@@ -752,4 +752,5 @@ email: [[email protected]](mailto:[email protected])
 | | | | | | |
 | 1108 | [Defanging an IP Address](https://leetcode.com/problems/defanging-an-ip-address/) | [无] | [C++](1108-Defanging-an-IP-Address/cpp-1108/) | | |
 | 1109 | [Corporate Flight Bookings](https://leetcode.com/problems/corporate-flight-bookings/) | [无] | [C++](1109-Corporate-Flight-Bookings/cpp-1009/) | | |
+| 1110 | [Delete Nodes And Return Forest](https://leetcode.com/problems/delete-nodes-and-return-forest/) | [无] | [C++](1110-Delete-Nodes-And-Return-Forest/cpp-1110/) | | |
 | | | | | | |