#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int N = 505;
int n, m, a, b, i, j, x, y;
ll mat[N][N], sm, tmp, ans;
ll f(int y){
return mat[x][y] - mat[x][j - 1] - mat[i - 1][y] + mat[i - 1][j - 1];
}
int main(){
ios_base::sync_with_stdio(0);
cin.tie(0); cout.tie(0);
cin >> n >> m >> a >> b;
for (i = 1; i <= n; i ++){
for (j = 1; j <= m; j ++){
cin >> mat[i][j];
mat[i][j] += mat[i - 1][j];
mat[i][j] += mat[i][j - 1];
mat[i][j] -= mat[i - 1][j - 1];
}
}
if (b < a) swap(a, b);
ans = 1e18;
for (i = 1; i <= n; i ++){
for (j = 1; j <= m; j ++){
y = j;
for (x = i; x <= n; x ++){
while (y + 1 <= m and f(y + 1) <= b)
y++;
sm = f(y);
tmp = abs(a - sm) + abs(b - sm);
ans = min(ans, tmp);
if (y < m) sm = f(y + 1);
ans = min(ans, abs(a - sm) + abs(b - sm));
}
}
}
cout << ans << endl;
}
