Envío 1133

Código

#include <iostream>
#include <climits>
using namespace std;

int main() {
    int R,C;
    cin >> R >> C;
    
    int m[R][C];
    int sum[R][C];
    
    for (int r = 0; r < R; r++) {
        for (int c = 0; c < C; c++) {
            cin >> m[r][c];
        }
    }
    

    for (int r = 0; r < R; r++) {
        for (int c = 0; c < C; c++) {
        
            int total =  m[r][c];
            if (r-1 >= 0 && c-1 >= 0)
               total -= sum[r-1][c-1];
            if (r-1 >= 0)
               total += sum[r-1][c];
            if (c-1 >= 0)
               total += sum[r][c-1];
           sum[r][c ] = total;  
                
        }
    }
    
    
    int answer = INT_MIN;
    for (int r0 = 0; r0 < R; r0++) {
        for (int c0 = 0; c0 < C; c0++) {
            for (int r1 = r0; r1 < R; r1++) {
                for (int c1 = c0; c1 < C; c1++) {
                    
                    int result = sum[r1][c1];
                    if (r0-1 >= 0 && c0-1 >= 0) 
                        result += sum[r0-1][c0-1];
                    if (r0-1 >=0 )
                        result -= sum[r0-1][c1];
                    if (c0-1 >= 0)
                        result -= sum[r1][c0-1];
                    answer = max(answer, result);
                }
            }
        }
    }

    cout << answer << endl;
    
    return 0;
}