POJ 3480 John（SJ定理博弈）题解

#include<set>
#include<map>
#include<stack>
#include<cmath>
#include<queue>
#include<vector>
#include<cstdio>
#include<cstring>
#include<iostream>
#include<algorithm>
typedef long long ll;
const int maxn = 4747 + 10;
const int seed = 131;
const ll MOD = 1e9 + 7;
const int INF = 0x3f3f3f3f;
using namespace std;
int main(){
    int T, n;
    scanf("%d", &T);
    while(T--){
        scanf("%d", &n);
        int ans = 0, flag = 0, u;
        while(n--){
            scanf("%d", &u);
            ans ^= u;
            if(u > 1) flag = 1;
        }
        if(ans){
            if(flag) printf("John\n");
            else printf("Brother\n");
        }
        else{
            if(flag) printf("Brother\n");
            else printf("John\n");
        }
    }
    return 0;
}