#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#include <math.h>

int main() {
	int y = 0;
	long long int x, sum = 100;

	scanf("%lld", &x);
	while (1) {
		if (sum >= x) break;
		sum = (long long int)(sum*1.01);
		y++;
	}
	printf("%d",y);

	return 0;
}