#include<stdio.h>
#include<stdlib.h>
#include<string.h>
#include<stdbool.h>
#include<math.h>
#include<limits.h>
typedef long long ll;

int main(){
    ll X;
    scanf("%lld",&X);
    ll year = 0,money = 100;
    while(money < X){
        money *= 1.01;
        year++;
    }
    printf("%lld",year);
}
