#include <bits/stdc++.h>
using namespace std;
int main() {
  int vp, vd, t, f, c, ans = 0;
  double tempt;
  double curs = 0;
  cin >> vp >> vd >> t >> f >> c;
  curs = vp * t;
  if (vp >= vd) {
    cout << 0 << endl;
    return 0;
  }
  while (curs < c) {
    tempt = curs / (vd - vp);
    curs += tempt * vp;
    if (curs >= c)
      break;
    else
      curs += (tempt + f) * vp;
    ans++;
  }
  cout << ans << endl;
  return 0;
}
