#include<stdio.h>
int main()
{
	int a,b,c,s;
	scanf("%d%d%d",&a,&b,&c);
	s=a*0.2+b*0.3+c*0.5;
	printf("%d",s);
	return 0;
}
/**************************************************************
	Problem: 1565
	User: admin
	Language: C
	Result: Accepted
	Time:36 ms
	Memory:1144 kb
****************************************************************/