#include <stdio.h>

int main (void){
  int  x=0;
  int sum=100;
  int i=0;
  
  if ( scanf("%d",&x) == 1){
    while(sum <= x){
      sum *= 1.01;
      i++;
    }
  }
  printf("%d\n",i);
  

  return 0;
  
}
