#include <malloc.h>
#include <math.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>

//ABC165D
//ABC165C
//ABC165B

int main(void) {
  long long x, n, k, i=0, cou=0;
  double tmp=100;
  scanf(" %lld", &x);
  while(x>tmp){
    tmp=floor(tmp*101/100);
    i++;
  }
  printf("%lld", i);
}
