Maximum rectangle containing 1 in binary matrix

/*
Logic:
If we consider each row as a base and then find the maximum reactangle in histogram then you will get the maximum
rectange from the binary matrix.

*/
int largest_rectangle(int arr[],int n) {
       stack<pair<int,int>> st;
       st.push({0,-1});
       int ans=INT_MIN;
       for(int i=1;i<n;i++){
           while(st.size() && arr[st.top().first]>=arr[i]){
               ans=max((i-st.top().second-1)*arr[st.top().first],ans);
               st.pop();
           }
           if(st.size()==0){
               st.push({i,-1});
           }
           else{
               st.push({i,st.top().first});
           }
       }
        while(st.size()){
            ans=max(ans,(n-st.top().second-1)*arr[st.top().first]);
            st.pop();
        }
        return ans;
}
class Solution{
  public:
    int maxArea(int arr[MAX][MAX], int n, int m) {
        int ans=INT_MIN;
        for(int i=0;i<n;i++){
            if(i!=0){
                for(int j=0;j<m;j++)
                if(arr[i][j]!=0) arr[i][j]+=arr[i-1][j];
                else arr[i][j]=0;
            }
            ans=max(ans,largest_rectangle(arr[i],m));
        }
        return ans;
    }
};