leetcode

Solution to some Leetcode problems written in C++
git clone git://git.dimitrijedobrota.com/leetcode.git
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3212.cpp (684B)

      1 class Solution {
      2   public:
      3     int numberOfSubmatrices(const vector<vector<char>> &grid) const {
      4         const int n = size(grid), m = size(grid[0]);
      5         vector<vector<int>> x(n + 1, vector(m + 1, 0));
      6         vector<vector<int>> y(n + 1, vector(m + 1, 0));
      7         int res = 0;
      8 
      9         for (int i = 1; i <= n; i++) {
     10             for (int j = 1; j <= m; j++) {
     11                 x[i][j] = x[i - 1][j] + x[i][j - 1] - x[i - 1][j - 1] + (grid[i - 1][j - 1] == 'X');
     12                 y[i][j] = y[i - 1][j] + y[i][j - 1] - y[i - 1][j - 1] + (grid[i - 1][j - 1] == 'Y');
     13                 if (x[i][j] > 0 && x[i][j] == y[i][j]) res++;
     14             }
     15         }
     16 
     17         return res;
     18     }
     19 };