#include <bits/stdc++.h>
using namespace std;
double vp, vd, t, f, c;
int ans;
int main() {
  scanf("%lf%lf%lf%lf%lf", &vp, &vd, &t, &f, &c);
  if (vp >= vd)
    printf("0\n");
  else {
    double now = 0.0, overtake = 0.0;
    while (now < c) {
      overtake = 1.0 * vp * t / (vd - vp);
      now = vp * (t + overtake);
      ans++;
      t += 2 * now / vd + f;
    }
    printf("%d\n", ans - 1);
  }
  return 0;
}
