#include<stdio.h>

int main(void){
	double p,q=99.0f,t,nt,r;
	scanf("%lf",&p);p/=100;
	t = p*q;
	nt =(100 - p)*(100 - q);
	printf("%.13lf\n",t * 100/(t+nt));
	return 0;
}