#include <bits/stdc++.h>

#define pb push_back

using namespace std;

const int maxN = (int)1e4;

int n, m, r, c;

int maxSum;

vector<vector<int>> a;

int s[maxN + 5];

int st[maxN + 5];

void bkt(int p) {
  for (int i = st[p - 1] + 1; i <= n; i++) {
    st[p] = i;
    for (int j = 1; j <= m; j++) {
      s[j] -= a[i][j];
    }
    if (p == r) {
      vector<int> cs;
      for (int j = 1; j <= m; j++) {
        cs.pb(s[j]);
      }
      sort(cs.begin(), cs.end());
      int sum = 0;
      for (int j = c; j < m; j++) {
        sum += cs[j];
      }
      maxSum = max(maxSum, sum);
    } else {
      bkt(p + 1);
    }
    for (int j = 1; j <= m; j++) {
      s[j] += a[i][j];
    }
  }
}

int main() {
  freopen("elimin.in", "r", stdin);
  freopen("elimin.out", "w", stdout);
  scanf("%d %d %d %d", &n, &m, &r, &c);
  a.resize(n + 1);
  for (int i = 1; i <= n; i++) {
    a[i].resize(m + 1);
    for (int j = 1; j <= m; j++) {
      scanf("%d", &a[i][j]);
    }
  }
  for (int i = 1; i <= n; i++) {
    for (int j = 1; j <= m; j++) {
      s[j] += a[i][j];
    }
  }
  bkt(1);
  printf("%d\n", maxSum);
  return 0;
}