#include <bits/stdc++.h>
using namespace std;
int ToInt(string& s, int len) {
  int r = 0;
  for (int i = 0, max_ = (len); i < max_; ++i) {
    r *= 10;
    r += s[i] - '0';
  }
  return r;
}
int GCD(int a, int b) { return b != 0 ? GCD(b, a % b) : a; }
int LCM(int a, int b) { return a * (b / GCD(a, b)); }
long long Pow(long long n, long long e) {
  if (e == 0) return 1;
  if (e == 1)
    return n;
  else if (e & 1) {
    long long t = Pow(n, e / 2);
    return n * t * t;
  } else {
    long long t = Pow(n, e / 2);
    return t * t;
  }
}
int vp, vd, t, f, c;
bool IsOK(int b) {
  if (vp >= vd) return true;
  double pos = t * vp;
  while (pos < c) {
    double time = pos / (double)(vd - vp);
    pos += time * vp;
    if (pos >= c) break;
    --b;
    if (b < 0) return false;
    pos += (f + time) * vp;
  }
  return true;
}
int main() {
  scanf("%d %d %d %d %d", &vp, &vd, &t, &f, &c);
  int minB = 0, maxB = 10000, currB, res;
  while (minB <= maxB) {
    currB = (minB + maxB) / 2;
    if (IsOK(currB)) {
      res = currB;
      maxB = currB - 1;
    } else
      minB = currB + 1;
  }
  printf("%d\n", res);
  return 0;
}
