#include <inttypes.h>
#include <math.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main(void)
{
    uintmax_t X;
    uintmax_t a = 100, y = 0;

    scanf("%ju", &X);

    while (a < X) {
        a += a / 100;
        y++;
    }

    printf("%ju\n", y);

    return 0;
}
