#include<bits/stdc++.h>
using namespace std;
int main(){
    double a,b;
    cin>>a;
    b=a*0.4463;
    if(a-150>0)b+=(a-150)*0.4663-(a-400)*0.4663;
    if(a-400>0)b+=(a-400)*0.5663;
    printf("%.1lf",b);
    return 0;
}