#include <stdio.h>
#include <stdlib.h>

int main(void)
{
    long x = 0;
    long sum = 100;
    long money = 100;
    int year = 0;

    scanf("%ld",&x);

    while(x > sum){
        sum = money * 1.01;
        year++;
        money = sum;
    }
    printf("%d\n",year);

    return 0;
}