Envío 1837

Código

#include <iostream>
#include <cstring>
#include <cstdio>
#include <cmath>
#include <queue>
#include <set>
#include <map>
#include <vector>
#include <stack>
#include <algorithm>
using namespace std;

int main()
{
    int f, c;
    int m[51][51];
    int p[51][51];
    int res = -10000000;
    
    cin>>f>>c;
    for(int i = 0; i < f; i++)
    {
        for(int j = 0; j < c; j++)
        {
            cin>>m[i][j];
            if(i==0 && j==0) p[i][j] = m[i][j];
            else if(i==0) p[i][j] = p[i][j-1] + m[i][j];
            else if(j==0) p[i][j] = p[i-1][j] + m[i][j];
            else p[i][j] = p[i-1][j] + p[i][j-1] - p[i-1][j-1] + m[i][j];
        }
    }
    
    int suma = 0;
    for(int i0 = 0; i0 < f; i0++)
    {
        for(int j0 = 0; j0 < c; j0++)
        {
            for(int i1 = i0; i1 < f; i1++)
            {
                for(int j1 = j0; j1 < c; j1++)
                {
                    if(i0==0 && j0==0) suma = p[i1][j1];
                    else if (i0 == i1 && j0 == j1) suma = m[i0][j0];
                    else if(i0==0) suma = p[i1][j1] - p[i1][j0-1];
                    else if(j0==0) suma = p[i1][j1] - p[i0-1][j1];
                    else suma = p[i1][j1] - p[i0-1][j0-1];
                    //cout<<"suma de "<<i0<<", "<<j0<<" hasta "<<i1<<", "<<j1<<" es = "<<suma<<endl;
                    res = max(suma, res);
                }
            }
        }
        //cout<<endl;
    }

    cout<<res<<endl;
    return 0;
}