#include<iostream> #include<cstdio> using namespace std; int main() { int d; double y; cin>>d; if(d<=150) y=d*0.4463; if(d>150&&d<=400) y=150*0.4463+(d-150)*0.4663; if(d>400) y=150*0.4463+250*0.4663+(d-400)*0.5663; printf("%.1f",y); return 0; }