BZOJ 1299: [LLH邀请赛]巧克力棒 [组合游戏]

#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>
#include <cmath>
using namespace std;
typedef long long ll;
const int N=15;
inline int read(){
char c=getchar();int x=0,f=1;
while(c<'0'||c>'9'){if(c=='-')f=-1;c=getchar();}
while(c>='0'&&c<='9'){x=x*10+c-'0';c=getchar();}
return x*f;
}
int n,a
;
bool solve(){
int All=1<<n;
for(int s=1;s<All;s++){
int sg=0;
for(int i=0;i<n;i++) if((1<<i)&s) sg^=a[i];
if(!sg) return true;
}
return false;
}
int main(){
//freopen("in","r",stdin);
int T=10;
while(T--){
n=read();
for(int i=0;i<n;i++) a[i]=read();
puts(solve() ? "NO" : "YES");
}
}