HDU 5795 A Simple Nim（SG打表找规律）

SG打表找规律
 1 #include<iostream>
 2 #include<cstdio>
 3 #include<cmath>
 4 #include<algorithm>
 5 #include<cstring>
 6 using namespace std;
 7 #define MAXN 10000
 8 int sg[MAXN],visit[MAXN];
 9 int getsg(int n)
10 {
11     int i,j;
12     if(sg[n]!=-1)
13     return sg[n];
14     memset(visit,0,sizeof(visit));
15     for(i=n-1;i>=0;i--)
16     visit[sg[i]]=1;
17     for(i=1;i<n;i++)
18     for(j=1;j<n;j++)
19     if(n-i-j>0)
20     visit[getsg(i)^getsg(j)^getsg(n-i-j)]=1;
21     for(i=0;i<=MAXN;i++)
22     if(!visit[i])
23     return sg[n]=i;
24 }
25 /*int main()
26 {
27     /**²âÊÔ´ò±í**/
28 
29     /*memset(sg,-1,sizeof(sg));
30     for(int i=0; i<50; i++)
31     {
32         printf("sg[%d] = %d
",i,getsg(i));
33     }
34     return 0;
35 }*/
36 int main()
37 {
38     int t,n,x;
39     scanf("%d",&t);
40     while(t--)
41     {
42         scanf("%d",&n);
43         int ans=0;
44         for(int i=0;i<n;i++)
45         {
46             scanf("%d",&x);
47             if(x%8==0)
48             ans^=x-1;
49             else if((x+1)%8==0)
50             ans^=x+1;
51             else
52             ans^=x;
53         }
54         if(!ans)
55         printf("Second player wins.
");
56         else
57         printf("First player wins.
");
58     }
59     return 0;
60 }