#include<stdio.h>
#include <math.h>
int main (void)
{
 int b,i=0,X;
 double a=100;


    printf("X=");
	scanf("%d",&X);

while (a < X) {
    i++;
    a *= 1.01;
    a=floor(a);
}

printf("%d",i);

return 0;
}