#include <bits/stdc++.h>
using namespace std;
int main() {
  double p, d, t, f, c;
  scanf("%lf %lf %lf %lf %lf", &p, &d, &t, &f, &c);
  if (p >= d) return puts("0"), 0;
  double now = t * p, bizo = 0;
  while (now <= c) {
    double step = now / (d - p);
    if (now + p * step >= c) break;
    bizo++;
    now = now + (p * step) * 2;
    now += p * f;
    if (now >= c) break;
  }
  printf("%.0f\n", bizo);
  return 0;
}
