check.cpp 内容如下（作者太弱了，并没有实测）：

#include"testlib.h"
#include<bits/stdc++.h>
int main(int argc,char*argv[]){
	using namespace std;
    registerTestlibCmd(argc,argv);
    int H17=ans.readInt();
    if(H17==-1){
    	int n=ouf.readInt();
    	if(n==-1)
    		quitf(_ok,"The answer is correct: No solution, good luck!");
    	else
    		quitf(_wa,"The answer is wrong: Your output isn't no solution, but the answer is.");
	}
	int n=inf.readInt(),cnt;
    vector<int>s(n,0),answ(n<<1,0),cur(n,0);
    queue<int>a;
    for(int i=0;i<(n<<1);i++)
    	answ[i]=inf.readInt();
    for(int i=0;i<n;i++)
    	a.push(answ[i]);
    for(int i=0;i<n;i++)
    	s[i]=ouf.readInt();
    for(int i=0;i<(n<<1);i++){
    	if(a.front()!=answ[i]){
    		quitf(_wa,"The answer is wrong: At the %d-th number, expect %d but %d found.",i,answ[i],a.front());
    		return 0;
		}
		cnt=n;
		while(!a.empty()){
			cur[--cnt]=a.front();
			a.pop();
		}
		for(int i=n-2;i>=0;i--)
			a.push(cur[i]);
		int nxt_int=0;
		for(int i=0;i<n;i++)
			nxt_int^=(cur[i]*s[i]);
		a.push(nxt_int);
	}
	quitf(_ok,"The answer is correct: All %d numbers are correct, good luck!",n<<1);
    return 0;
}

输入文件正常放，输出文件对于无解放 -1 否则随便放一个整数.