#include <bits/stdc++.h>
using namespace std;
int main() {
  int vp, vd, t, f, c, ans;
  double cc, d;
  scanf("%d%d%d%d%d", &vp, &vd, &t, &f, &c);
  if (vd <= vp) {
    printf("0\n");
    return 0;
  }
  d = vp * t;
  cc = c;
  ans = 0;
  while (1) {
    if (d + d / (vd - vp) * vp >= cc - 1e-9) break;
    ans++;
    d = d + (2 * d / (vd - vp) + f) * vp;
  }
  printf("%d\n", ans);
  return 0;
}
