#include <iostream>
#include <fstream>
#define  NMAX 101

using namespace std;
ifstream fin("elimin.in");
ofstream fout("elimin.out");

int a[NMAX][NMAX];
int first,summaxim,v[NMAX];
int N,M,R,C;
void write_sol()
{
    int sum=0;

    int suma=0;
    for(int i = 1; i <= N; i ++)
    {
        for(int j = 1; j <= M; j++)
            sum+=a[i][j]*v[i]*v[R+j];
    }
    if(sum>summaxim)
        summaxim=sum;
}
int answer(int k)
{
    if(k==R+C+1)
    {
        write_sol();
    }
    else
    {
        v[k]=1;
        answer(k+1);

        v[k]=0;
        answer(k+1);
    }
}
int main()
{
    fin>>N>>M>>R>>C;
    for(int i  = 1 ; i <= N ; i ++)
        for(int j =1 ; j <= M; j++)
            fin>>a[i][j];
    answer(1);
    fout<<summaxim;

    return 0;
}