#include<stdio.h>
int main()
{
    double m,n,t,s;
    scanf("%lf%lf%lf",&n,&m,&t);
    s=m+n+t;
    if(s>=200)
        printf("%.1lf",s*0.8);
    else
        printf("%.1lf",s*0.9);
    return 0;
}

/**************************************************************
	Problem: 1624
	User: admin
	Language: C
	Result: Accepted
	Time:14 ms
	Memory:1144 kb
****************************************************************/