#include <stdio.h>
int main()
{
	char ch;
	int i,n,in,holder;
	scanf("%c",&ch);
	scanf("%d",&n);
	if(n<=0) return 0;
	scanf("%d",&holder);
	for(i=1;i<n;i++)
	{
		scanf("%d",&in);
		switch(ch)
		{
			case '+': 
			case 'a':
				holder = holder + in;
				break;
			case '*': holder = holder * in; 
		}

	}
	if(ch == 'a') 
		printf ("%lf\n",(double) holder/n);
	else
		printf("%d\n",holder);
}