Be the Winner HDU杭电2509 【尼姆博弈】

http://acm.hdu.edu.cn/showproblem.php?pid=2509

Problem Description

Let's consider m apples divided into n groups. Each group contains no more than 100 apples, arranged in a line. You can take any number of consecutive apples at one time.
For example "@@@" can be turned into "@@" or "@" or "@ @"(two piles). two people get apples one after another and the one who takes the last is
the loser. Fra wants to know in which situations he can win by playing strategies (that is, no matter what action the rival takes, fra will win).

 

Input

You will be given several cases. Each test case begins with a single number n (1 <= n <= 100), followed by a line with n numbers, the number of apples in each pile. There is a blank line between cases.

 

Output

If a winning strategies can be found, print a single line with "Yes", otherwise print "No".

 

Sample Input

   
   
   
   

    
    
    
    2
2 2
1
3
   
   
   
   

 

Sample Output

   
   
   
   

    
    
    
    No
Yes
   
   
   
   

 

//这里用到博弈的知识

http://baike.baidu.com/link?url=o1BeXSvZyGiVosS_HwR7dvB5vDrroHL2aJNp9SmwxNpet_dPwtDCp8Th3QRmo03gp-WY8znVaFBnCCjC1iHHba

#include <stdio.h>
int main()
{
	int n;
	while(~scanf("%d",&n))
	{
		int flag=1;//判断是否全为一
		int sum=0,temp;
		for(int i=0;i<n;++i)
		{
			scanf("%d",&temp);
			sum^=temp;//判断是否为必输状态
			if(temp>1) flag=0;
		}
		if(flag==1)
		{
			if(n&1)
			{
				printf("No\n");
			}
			else printf("Yes\n");
		}
		else
		{
			if(sum==0) printf("No\n");
			else printf("Yes\n");
		}
	}
	return 0;
}