#include <bits/stdc++.h>
using namespace std;
int main() {
  double vp, vd, t, f, c;
  cin >> vp >> vd >> t >> f >> c;
  if (vp >= vd) {
    cout << "0\n";
    return 0;
  }
  int ct = 0;
  double loc_now = vp * t;
  loc_now += (loc_now * vp / (vd - vp));
  while (c - loc_now > 1e-06) {
    ++ct;
    double tt = loc_now / vd;
    tt += f;
    loc_now += (vp * tt);
    loc_now += (loc_now * vp / (vd - vp));
  }
  cout << ct << endl;
  return 0;
}
