#include <bits/stdc++.h>
static const int INF = std::numeric_limits<int>::max();
int main() {
  int vp, vd, t, f, c;
  std::cin >> vp >> vd >> t >> f >> c;
  if (vp >= vd) {
    std::cout << 0 << std::endl;
    return 0;
  }
  double dp = t * vp;
  int res = 0;
  while (dp + 1e-9 < c) {
    double tp = dp / (vd - vp);
    if (dp + tp * vp + 1e-9 >= c) {
      break;
    }
    ++res;
    double tt = tp + f;
    dp += (tp + tt) * vp;
  }
  std::cout << res << std::endl;
}
