#include<bits/stdc++.h>

using namespace std;

int main()

{

	char x,y;

	cin>>x;

	if (x<=150){

	y==x*0.4463;

	printf("%1f",y);}

	if(x>150&&x<=400){

	y==150*0.4463+(x-150)*0.4663;

	printf("%1f",y);}

	if(x>400){

	y==150*0.4463+(x-150)*0.4663+(x-400)*0.5663;

	printf("%1f",y);}

	return 0;

}