#include <bits/stdc++.h>
using namespace std;
int L, R, t, f, c;
int main() {
  cin >> L >> R >> t >> f >> c;
  if (L >= R) {
    printf("0\n");
    return 0;
  }
  int now = t, ans = 0;
  double d = L * t;
  while (d < c) {
    double dt = d / (R - L);
    d = d + dt * L;
    if (d - c > -1e-8) break;
    ++ans;
    d = d + (dt + f) * L;
  }
  cout << ans << endl;
  return 0;
}
