#include <iostream>
#include <fstream>
#include <vector>
#define MAX_POSSIBLE 2147483647
using namespace std;

vector< vector<short> > mat;
vector<bool> eliminln;
vector<bool> eliminclmn;
vector< vector<short> > temp_ln;
short m,n,R,C,a;
int result,result_max=0;
long minclmn=MAX_POSSIBLE;

int sum_clmn(short z)
 {
     long s=0;
     for(short i=0;i<m;i++)
         s+=mat[i][z];
     return s;
 }

void elimin_ln(short sz)
 {
     for(short i=0;i<n;i++)
         mat[sz][i]=0;
     eliminln[sz]=true;
 }

void elimin_clmn(short h)
 {
     for(short i=0;i<m;i++)
         mat[i][h]=0;
     eliminclmn[h]=true;
 }

int min_clmn()
 {
     short p;
     long d;
     for(short i=0;i<n;i++)
         {
             d=sum_clmn(i);
             if(d<=minclmn && eliminclmn[i]!=true)
                 {
                     p=i;
                     minclmn=d;
                 }
         }
     minclmn=MAX_POSSIBLE;
     return p;
 }

int sum()
 {
     long b=0;
     for(short i=0;i<m;i++)
         for(short j=0;j<n;j++)
             b+=mat[i][j];
     return b;
 }

void backt_ln(short k)
 {
     if(k>R)
         {
             for(short l=0;l<C;l++)
                 {
                     a=min_clmn();
                     if(eliminclmn[a]!=true)
                         {
                             result=sum();
                             result=result-sum_clmn(a);
                             eliminclmn[a]=true;
                         }

                 }
             if(result>result_max)
                 result_max=result;
         }
     else
         for(short i=0;i<m;i++)
             if(eliminln[i]!=true)
              {
                  for(short j=0;j<n;j++)
                      temp_ln[i][j]=mat[i][j];
                  elimin_ln(i);
                  backt_ln(k+1);
                  for(short j=0;j<n;j++)
                      mat[i][j]=temp_ln[i][j];
                  eliminln[i]=false;
                  for(short l=0;l<n;l++)
                      if(eliminclmn[l]=true)
                          eliminclmn[l]=false;
              }
 }

int main()
 {
     ifstream f("elimin.in");
     ofstream g("elimin.out");

     f>>m>>n>>R>>C;
     mat.resize(m);
     for(short i=0;i<m;i++)
         mat[i].resize(n);
     for(short i=0;i<m;i++)
         for(short j=0;j<n;j++)
             f>>mat[i][j];
     eliminln.resize(m);
     eliminclmn.resize(n);
     temp_ln.resize(m);
     for(short i=0;i<m;i++)
         temp_ln[i].resize(n);

     backt_ln(1);
     g<<result_max;
     cout<<result_max;
 }