#include<bits/stdc++.h>
using namespace std;
int main(){
	float x,y,z,h;
	cin>>x>>y>>z;
	if(x+y+z>=200){
	    h=(x+y+z)*0.8;
	    printf("%.1f",h);
	}else{
		h=(x+y+z)*0.9;
		printf("%.1f",h);
	}
}
/**************************************************************
	Problem: 1624
	User: wangyiyang
	Language: C++
	Result: Accepted
	Time:17 ms
	Memory:2072 kb
****************************************************************/