1、

#include <iostream>
#include <cstdio>
using namespace std;
int main()
{
	int n;
	double s;
	scanf("%d",&n);
	if(n<=150)  s=n*0.4463;
	else if(n<=400&&n>=151)  s=150*0.4463+(n-150)*0.4663;
	else if(n>=401)  s=150*0.4463+250*0.4663+(n-400)*0.5663;
	printf("%.1lf",s);
	return 0;
 }