add 935

src/0935-Knight-Dialer/0935.cpp

@@ -0,0 +1,38 @@
+#include <iostream>
+#include <vector>
+#include <numeric>
+using namespace std;
+
+static int x = []() {std::ios::sync_with_stdio(false); cin.tie(0); return 0; }();
+class Solution 
+{
+public:
+    int knightDialer(int N) 
+    { 
+        vector<long long> result(10, 1);
+        vector<long long> mem(10);
+        long long mod = 1e9+7;
+        for (int i = 1; i < N; i++)
+        {
+            mem[0] = (result[4] + result[6]) % mod;
+            mem[1] = (result[6] + result[8]) % mod;
+            mem[2] = (result[7] + result[9]) % mod;
+            mem[3] = (result[4] + result[8]) % mod;
+            mem[4] = (result[0] + result[3] + result[9]) % mod;
+            mem[5] = 0;
+            mem[6] = (result[0] + result[1] + result[7]) % mod;
+            mem[7] = (result[6] + result[2]) % mod;
+            mem[8] = (result[1] + result[3]) % mod;
+            mem[9] = (result[2] + result[4]) % mod;
+            result = mem;
+        }
+        return accumulate(result.begin(), result.end(), 0, 
+        [=](long long s, long long n) { return int((s + n) % mod);});
+    }
+};
+int main()
+{
+    int N = 2;
+    cout << Solution().knightDialer(N);
+    return 0;
+}

src/0935-Knight-Dialer/0935.py

@@ -0,0 +1,28 @@
+from ctypes import c_uint32
+class Solution:
+    hops = [(c_uint32 * 4)(4, 2, 2, 1)]
+    def knightDialer(self, N):
+        """
+        :type N: int
+        :rtype: int
+        """
+        if N == 1:
+            return 10
+
+        mod = 10**9 + 7
+
+        if N <= len(self.hops):
+            H = self.hops[N - 1]
+        else:
+            H = self.hops[-1]
+            for _ in range(len(self.hops), N):
+                H = (c_uint32 * 4)(2*(H[1] + H[2]), 2*H[3] + H[0], H[0], H[1])
+                for i in (0, 1, 2, 3):
+                        H[i] %= mod
+                self.hops.append(H)
+
+        return sum(H) % mod
+
+if __name__ == "__main__":
+    N = 2
+    print(Solution().knightDialer(N))