#include <bits/stdc++.h>
using namespace std;
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  long double vp, vd, c, f, t, count = 0;
  cin >> vp >> vd >> t >> f >> c;
  if (vp >= vd) {
    cout << 0;
    return 0;
  }
  long double t1 = (vp * t) / (vd - vp);
  if (vp * (t + t1) >= c) {
    cout << 0;
    return 0;
  }
  count++;
  long double t2 = t1;
  long double x = vp * (t1 + t);
  while (1) {
    t2 = ((x + vp * (t1 + f)) / (vd - vp));
    count++;
    x += vp * (t1 + t2 + f);
    if (x >= c) {
      cout << (count - 1);
      return 0;
    }
    t1 = t2;
  }
  cout << count;
  return 0;
}
