#include <bits/stdc++.h>
int main() {
  long long int n, m, k, l, sum, x;
  while (~scanf("%lld%lld%lld%lld", &n, &m, &k, &l)) {
    l += k;
    if (l % m == 0)
      sum = l / m;
    else
      sum = l / m + 1;
    x = sum * m;
    if (x > n)
      printf("-1\n");
    else
      printf("%lld\n", sum);
  }
  return 0;
}
