leetcode

1727.cpp (640B)

 class Solution {
   public:
     int largestSubmatrix(vector<vector<int>> &matrix) {
         const int n = matrix.size(), m = matrix[0].size();
         vector<int> height(m, 0);
         int ans = 0;
 
         for (int i = 0; i < n; i++) {
             for (int j = 0; j < m; j++) {
                 if (matrix[i][j] == 0)
                     height[j] = 0;
                 else
                     height[j] += 1;
             }
 
             vector<int> order = height;
             sort(begin(order), end(order));
 
             for (int j = 0; j < m; j++)
                 ans = max(ans, order[j] * (m - j));
         }
         return ans;
     }
 };