#include<cstdio>
#include<algorithm>
#include<cmath>
using namespace std;
int n,m,r,c,a[20][20],p[20],dp[20][20],ans;
int v[20][20];
int val(int x,int y){
	int ans=0;
	if (x)
	for (int i=1;i<=r;i++)
		ans+=abs(a[p[i]][x]-a[p[i]][y]);
	for (int i=2;i<=r;i++)
		ans+=abs(a[p[i-1]][y]-a[p[i]][y]);
	return ans;
}
void DP(){
	for (int i=0;i<=m;i++)
	for (int j=i+1;j<=m;j++)
		v[i][j]=val(i,j);
	for (int i=1;i<=c;i++)
	for (int j=0;j<=m;j++)
		dp[i][j]=99999999;
	for (int i=0;i<c;i++)
	for (int j=0;j<=m;j++)
	for (int k=j+1;k<=m;k++)
		dp[i+1][k]=min(dp[i+1][k],dp[i][j]+v[j][k]);
	for (int j=0;j<=m;j++)
		ans=min(ans,dp[c][j]);
}
void ss(int x,int cnt)
{
	if (cnt==r){
		DP();return;
	}
	for (int i=x;i<=n;i++)
		p[cnt+1]=i,ss(i+1,cnt+1);
}
int main()
{
	freopen("submatrix.in","r",stdin);
	freopen("submatrix.out","w",stdout);
	scanf("%d%d%d%d",&n,&m,&r,&c);
	for (int i=1;i<=n;i++)
	for (int j=1;j<=m;j++)
		scanf("%d",&a[i][j]);
	ans=99999999;ss(1,0);
	printf("%d\n",ans);
	return 0;
}