#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <math.h>
int main(void){
    int x,y=0,money=100;
    scanf("%d",&x);
    while(money<x){
        money = money * 1.01;
        money = floor(money);
        y++;
    }
    printf("%d",y);
    return 0;
}