leetcode

0 class Solution {

1 static const int MOD = 1E9 + 7;

2 static int dp[51][51][51];

3

4 public:

5 Solution() { memset(dp, 0xFF, sizeof(dp)); }

6 int findPaths(const int m, const int n, const int moves, const int row, const int col) const {

7 if (!moves) return 0;

8 if (dp[moves][row][col] != -1) return dp[moves][row][col];

9 int res = 0;

10

11 static int offset[] = {-1, 0, 1, 0, -1};

12 for (int k = 0; k < 4; k++) {

13 const int x = row + offset[k];

14 const int y = col + offset[k + 1];

15 if (x < 0 || y < 0 || x >= m || y >= n)

16 res++;

17 else

18 res = (res + findPaths(m, n, moves - 1, x, y)) % MOD;

19 }

20

21 return dp[moves][row][col] = res;

22 }

23 };

24

25 int Solution::dp[51][51][51];