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

int main(void) {

    unsigned long money;
    scanf("%lu",&money);
    unsigned long max = money;
    unsigned long internal_m = 100;

    unsigned long count = 0;

    while(internal_m < max){
        internal_m = (unsigned long)((long double)internal_m * 1.01);
        count++;
    }

    printf("%lu\n",count);

    return 0;
}