#include <stdio.h>

int main(void)
{
  long long int x,  year = 0, possession = 100;
  double interest = 1.01;

  scanf("%lld", &x);

  while (x > possession)
    {
      possession = (long long int)(possession * interest);
      year++;
    }

  printf("%lld", year);

  return 0;

}
