accumulate the height
\nclass Solution {\npublic:\n    int largestSubmatrix(vector<vector<int>>& mt) {\n    \n        int n = mt.size();\n        int m = mt[0].size();\n        int r
```\nclass Solution {\npublic:\n    int largestSubmatrix(vector<vector<int>>& mt) {\n    \n        int n = mt.size();\n        int m = mt[0].size();\n        int res = 0;\n        for(int i = 0;i<n;i++)\n        {\n            for(int j=0;j<m;j++)\n            {\n                if(mt[i][j] == 1 && i>0)\n                {\n                    mt[i][j] += mt[i-1][j];\n                }\n            }\n            \n            vector<int> temp  = mt[i];\n            sort(temp.begin(),temp.end(),greater<int>());\n            \n            for(int k = 0;k<m;k++)\n            {\n                int b = k+1;\n                int h = temp[k];\n                res = max(res, b*h);\n            }\n            \n        }\n        \n        return res;\n        \n        \n    }\n};\n```
['C']