P2599 [ZJOI2009]取石子游戏

https://www.luogu.com.cn/problem/P2599

全部不为1的时候

如果面临两部分相等，那么后手赢

否则先手赢

#include<bits/stdc++.h>
using namespace std;
int t,n,a1,an,c;
int main() {
    //freopen("in","r",stdin);
    ios::sync_with_stdio(0);
    cin >> t;
    while(t--){
        cin >> n;
        for(int i = 1; i <= n; i++){
            int g;
            cin >> g;
            if(g == 1) c++;
            if(i == 1) a1 = g;
            if(i == n) an = g;
        }
        if(c == n){
            if(n & 1) cout << 1 << endl;
            else cout << 0 << endl;
        }else{
            if(abs(a1 - an) <= 1 && a1 != 1 && an != 1)
                cout << 0 << endl;
            else cout << 1 << endl;
        }
    }
    return 0;
}