#include <stdio.h>

const float PERCENT = 1.01;

int main(int argc, const char **argv)
{
    long start = 100l, goal = 0l, year = 0l;

    fscanf(stdin, "%ld", &goal);

    while (1)
    {
        year++;
        start *= PERCENT;
        if ( start >= goal ) break;
    }

    fprintf(stdout, "%ld\n", year);
    return 0;
}