1026 居民电费

#include<iostream>
#include<iomanip>
#include<math.h>
using namespace std;
int main(){
double x,y,s;
cin>>x>>y;
s=0.538*x+0.03*y;
cout<<setiosflags(ios::fixed)<<setprecision(2)<<s<<endl;
return 0;
}