#include <bits/stdc++.h>
using namespace std;
int main() {
  int vp, vd, t, f, c;
  scanf("%d %d %d %d %d", &vp, &vd, &t, &f, &c);
  if (vp > vd)
    printf("0\n");
  else {
    double tp = (double)c / vp, tcur = 0;
    int cont = 0;
    while (true) {
      if (cont == 0)
        tp -= t, tcur += t;
      else
        tp -= f, tcur += f;
      if (tp <= 0) break;
      double tcatch = (tcur * vp) / (vd - vp);
      tp -= tcatch;
      tcur += tcatch;
      if (tp <= 0) break;
      tp -= tcatch;
      tcur += tcatch;
      ++cont;
    }
    printf("%d\n", cont);
  }
  return 0;
}
