#include <bits/stdc++.h>
using namespace std;
const int MOD = 1000000007;
int main() {
  long long n, m, k, l, ans = 0;
  cin >> n >> m >> k >> l;
  if (n < m || n < l + k) return cout << "-1\n", 0;
  long long cnt = (l + k + m - 1) / m;
  if (cnt * m > n)
    return cout << "-1\n", 0;
  else
    cout << cnt << "\n";
  return 0;
}
