#include <bits/stdc++.h>
using namespace std;
long long gcd(long long a, long long b) { return a ? gcd(b % a, a) : b; }
void swap(char* a, char* b) {
  char temp = *a;
  *a = *b;
  *b = temp;
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  long long n, k, l, m;
  cin >> n >> m >> k >> l;
  long long coins = k + l + m - 1;
  coins /= m;
  if (coins * m > n) {
    cout << "-1\n";
  } else {
    cout << coins << endl;
  }
  return 0;
}
