#include <bits/stdc++.h>
using namespace std;
int main() {
  double Vp, Vd, t, delay, c, rtrns = 0, hours = 0;
  cin >> Vp >> Vd >> t >> delay >> c;
  if (Vd <= Vp) {
    cout << 0;
    return 0;
  }
  double pDistance = Vp * t;
  while (pDistance < c) {
    double time = pDistance / (Vd - Vp);
    pDistance += time * Vp;
    if (pDistance >= c) break;
    rtrns++;
    double bktime = pDistance / Vd + delay;
    pDistance += bktime * Vp;
  }
  cout << rtrns << endl;
}
