FZU 2264 Card Game (First Edition)

http://acm.fzu.edu.cn/problem.php?pid=2264

玄学求期望。。。

#include<iostream>
#include<cstdio>
#include<cstring>
#define iloveu return 0
#define wangxingyi main
using namespace std;
int wangxingyi(){
		 int t;
		 cin>>t;
		 int cs=1;
		 while(t--)
		 {
		 	int m;
		 	int a;
		 	cin>>m;
		 	for(int i=-m;i<m;i++)
		 	scanf("%d",&a);
		 	printf("Case %d: ",cs++);
		 	if(m%2==0)printf("%d.00\n",m/2);
		 	else printf("%d.50\n",m/2);
		 }
	iloveu;
}