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

int main() {

    long x;

    scanf("%ld", &x);

    double mysum = 100;
    int cnt = 0;
    while (mysum < x) {

        mysum = floor(mysum * 1.01);

        cnt++;
        
    }

    printf("%d", cnt);

    return 0;
}
