#include <bits/stdc++.h>
using namespace std;
int vp, vd, t, f, c;
int main() {
  scanf("%d%d%d%d%d", &vp, &vd, &t, &f, &c);
  double cnt = t * vp, ans = 0;
  while (vd > vp && cnt < c - 1e-7) {
    cnt += (double)cnt / (vd - vp) * vp;
    if (cnt >= c - 1e-7) break;
    ans++;
    cnt += ((double)cnt / vd + f) * vp;
  }
  cout << ans << endl;
  return 0;
}
