#include <bits/stdc++.h>
using namespace std;
int main() {
  int vp, vd, t, f, c;
  cin >> vp >> vd >> t >> f >> c;
  if (vp >= vd) {
    cout << 0;
    return 0;
  }
  double x = vp * t;
  if (x >= c) {
    cout << 0;
    return 0;
  }
  int b = 0;
  while (1) {
    double dt = x / (vd - vp);
    x = x + vp * dt;
    if (x >= c) {
      cout << b;
      return 0;
    }
    b++;
    dt = x / vd + f;
    x = x + vp * dt;
  }
}
