#include <bits/stdc++.h>

using namespace std;
long long N, M, K, L;

long long v[40][40][40][40];
long long a, b, c, d;
long long ans=2000000000;
long long solve(long long i, long long j, long long k, long long l)
{
    return v[i+1][j+b][k+c][l+d] - v[i][j][k+c][l+d] + v[i][j+b][k+c][l+d] + v[i+a][j][k+c][l+d]
                                 +v[i+a][j+b][k][l+d] + v[i][j][k][l+d] - v[i][j+b][k][l+d] - v[i+a][j][k][l+d]
                                 +v[i+a][j+b][k+c][l] + v[i+a][j+b][k+c][l] - v[i][j+b][k+c][l] - v[i+a][j][k+c][l];
}

int main()
{
    cin>>N>>M>>K>>L;

     for(long long i=1; i<=N; i++)
         for(long long j=1; j<=M; j++)
             for(long long k=1; k<=K; k++)
                 for(long long l=1; l<=L; l++)
                     scanf("%d", &v[i][j][k][l]);

     for(long long i=1; i<=N; i++)
         for(long long j=1; j<=M; j++)
             for(long long k=1; k<=K; k++)
                 for(long long l=1; l<=L; l++)
                 {
                    v[i][j][k][l]=v[i][j][k][l] - v[i-1][j-1][k][l] + v[i-1][j][k][l] + v[i][j-1][k][l]
                                 +v[i][j][k-1][l] + v[i-1][j-1][k-1][l] - v[i-1][j][k-1][l] - v[i][j-1][k-1][l]
                                 +v[i][j][k][l-1] + v[i-1][j-1][k][l-1] - v[i-1][j][k][l-1] - v[i][j-1][k][l-1];
                                 //-v[i][j][k-1][l-1] - v[i-1][j-1][k-1][l-1] + v[i-1][j][k-1][l-1] + v[i][j-1][k-1][l-1]                 }
                }

     for(long long i=1; i+a<=N; i++)
         for(long long j=1; j+b<=M; j++)
             for(long long k=1; k+c<=K; k++)
                 for(long long l=1; l+d<=L; l++)
                 {
                    long long mm=solve(i, j, k, l);
                    if(mm<ans) mm=ans;
                 }

                 cout<<ans<<'\n';



    return 0;
}