hdu 2999 Stone Game, Why are you always there? 博弈论

SG函数应用！！

代码如下：

 #include<cstdio>
 #include<cstring>
 #include<iostream>
 #include<cmath>
 #include<algorithm>
 using namespace std;
 int sg[],a[],n;
 int get_sg(int m)
 {
     if(sg[m]!=-) return sg[m];
     bool vis[];
     memset(vis,,sizeof(vis));
     for(int i=;i<n&&a[i]<=m;i++)
         for(int j=;j<=m-a[i]-j;j++){
         vis[get_sg(m-a[i]-j)^get_sg(j)]=;
     }
     int i=;
     while(vis[i]) i++;
     return sg[m]=i;
 }
 int main()
 {
     int i,j,m,p,k;
     while(scanf("%d",&n)!=EOF){
         for(i=;i<n;i++) scanf("%d",&a[i]);
         sort(a,a+n);
         for(i=j=;i<n;i++)
         if(a[i]!=a[j-]){
             a[j++]=a[i];
         }
         n=j;
         scanf("%d",&m);
         memset(sg,-,sizeof(sg));
         sg[]=;
         while(m--){
             scanf("%d",&k);
             puts(get_sg(k)?"":"");
         }
     }
     return ;
 }