#include <bits/stdc++.h>
using namespace std;
int main() {
  double p, d, t, f, c;
  cin >> p >> d >> t >> f >> c;
  double k = d - p, x = p * t, r = 0;
  if (k > 0)
    while (1)
      if ((x += x / k * p) >= c)
        break;
      else {
        r++;
        x += p * (x / d + f);
      }
  cout << r;
}
