#include <bits/stdc++.h>
using namespace std;
int main() {
  int vp, vd, t, f, c;
  cin >> vp >> vd >> t >> f >> c;
  int vs = vd - vp;
  if (vp > vd) {
    cout << 0;
    return 0;
  }
  if (vp == vd) {
    cout << 0;
    return 0;
  }
  double d = vp * t;
  d += d / (1.0 * vs) * vp;
  cerr << d << endl;
  if (int(d) >= c) {
    cout << 0;
    return 0;
  }
  int ans = 1;
  while ((int)d < c) {
    d += (d / vd + f) * vp;
    d += (d / vs) * vp;
    if (d - c > -1e-12) {
      cout << ans;
      return 0;
    }
    ans++;
  }
  cout << ans << endl;
}
