#include<bits/stdc++.h>
using namespace std;
int main() {
	float a,b,c,q,z;
	cin>>a>>b>>c;
	z=a+b+c;
	if(z>=200){
		q=z*0.8;
	}else{
		q=z*0.9;
	}
	printf("%.1f",q);
    return 0;
}

/**************************************************************
	Problem: 1624
	User: huangcanwu
	Language: C++
	Result: Accepted
	Time:26 ms
	Memory:2072 kb
****************************************************************/