#include<stdio.h>

int main(void)
{
	unsigned long int a, b, c;
	int i = 0;

	b = 100;

	scanf("%ld", &a);

	do {
		b = (long int)(b * 1.01);
		i++;
	} while (b < a);

	printf("%ld", i);

	return 0;
}