SIMPLE SOLUTION 6MS FASTER THAN 100%
JAVA CODE IS:\n#    \n\nclass Solution {\n    int find(int arr[]){\n        Arrays.sort(arr);\n        int res=0;\n        for(int i=0;i<arr.length;i++)\n      
JAVA CODE IS:\n#    \n```\nclass Solution {\n    int find(int arr[]){\n        Arrays.sort(arr);\n        int res=0;\n        for(int i=0;i<arr.length;i++)\n            res=Math.max(res,arr[i]*(arr.length-i));\n        return res;\n    }\n    public int largestSubmatrix(int[][] matrix) {\n        //size of matrix is n*m\n     int n=matrix.length;\n        if(n==0) return 0;\n     int m=matrix[0].length;\n        for(int j=0;j<m;j++){\n            for(int i=1;i<n;i++)\n                matrix[i][j]=matrix[i][j]==0 ? 0 : 1+matrix[i-1][j];\n        }\n      int res=0;\n     for(int arr[] : matrix){\n          res=Math.max(res,find(arr));\n       }\n        return res;\n }\n}\n```\n***PLEASE,UPVOTE IF THIS IS HELPFUL***
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