#include <stdio.h>
main(){
    double k =100;
    double N;
    int a,b ;
    b=0;
    scanf("%d",&a);
    while(N >= a){
        b+=1;
        if(b = 0){
            N = k +(fmod(k * 1.01), 100);
        } else {
        N =N+(fmod(N * 1.01),100);
        }
    }
    return b;
}

