#include <bits/stdc++.h>
using namespace std;
const int NUM = 2e6 + 5;
int main() {
  int t = 1;
  while (t--) {
    long long int n, m, k, l;
    cin >> n >> m >> k >> l;
    long long int coins = (l + k);
    if (coins % m)
      coins = coins / m + 1;
    else
      coins = coins / m;
    if (coins * m > n)
      cout << -1;
    else
      cout << coins;
  }
}
