leetcode

0 class Solution {

1 public:

2 int numberOfSubmatrices(const vector<vector<char>> &grid) const {

3 const int n = size(grid), m = size(grid[0]);

4 vector<vector<int>> x(n + 1, vector(m + 1, 0));

5 vector<vector<int>> y(n + 1, vector(m + 1, 0));

6 int res = 0;

7

8 for (int i = 1; i <= n; i++) {

9 for (int j = 1; j <= m; j++) {

10 x[i][j] = x[i - 1][j] + x[i][j - 1] - x[i - 1][j - 1] + (grid[i - 1][j - 1] == 'X');

11 y[i][j] = y[i - 1][j] + y[i][j - 1] - y[i - 1][j - 1] + (grid[i - 1][j - 1] == 'Y');

12 if (x[i][j] > 0 && x[i][j] == y[i][j]) res++;

13 }

14 }

15

16 return res;

17 }

18 };