#include <bits/stdc++.h>
using namespace std;
int main() {
  int vp, vd, t, f, c;
  cin >> vp >> vd >> t >> f >> c;
  if (vd < vp) {
    cout << 0;
    return 0;
  }
  int tmp = (vd - vp);
  int res = 0;
  double dis = t * vp;
  double crd = dis + dis * vp / tmp;
  while (crd < c) {
    res++;
    cerr << crd << '\n';
    dis = (((crd * 2) / vd) + f) * vp;
    crd += dis + dis * vp / tmp;
  }
  cout << res;
  {
    char _;
    cin >> _;
  }
  return 0;
}
