Go: package main

import "fmt"

func main() {
    var n, m int
    fmt.Scan(&n)

    u := make([]string, 300)

    for i := 0; i < n; i++ {
        fmt.Scan(&u[i])
    }

    fmt.Scan(&m)

    is_lock := true
    for i := 0; i < m; i++ {
        var t string
        fmt.Scan(&t)

        is_include := false
        for j := 0; j < n; j++ {
            if t == u[j] {
                is_include = true
                break
            }
        }
        if is_include == false {
            fmt.Printf("Unknown %s\n", t)
        } else if (is_lock) {
            fmt.Printf("Opened by %s\n", t)
            is_lock = false
        } else {
            fmt.Printf("Closed by %s\n", t)
            is_lock = true
        }
    }
}

C++: #include "bits/stdc++.h"
using namespace std;

//#define int long long
#define DBG 1
#define dump(o) if(DBG){cerr<<#o<<" "<<o<<endl;}
#define dumpc(o) if(DBG){cerr<<#o; for(auto &e:(o))cerr<<" "<<e;cerr<<endl;}
#define rep(i,a,b) for(int i=(a);i<(b);i++)
#define rrep(i,a,b) for(int i=(b)-1;i>=(a);i--)
#define each(it,c) for(auto it=(c).begin();it!=(c).end();it++)
#define all(c) c.begin(),c.end()
const int INF = sizeof(int) == sizeof(long long) ? 0x3f3f3f3f3f3f3f3fLL : 0x3f3f3f3f;
const int MOD = (int)(1e9 + 7);

signed main() {
	int N; cin >> N;
	vector<string> U(N); rep(i, 0, N) { cin >> U[i]; }
	int M; cin >> M;
	vector<string> T(M); 
	bool isopened = false;
	rep(i, 0, M) {
		cin >> T[i];
		if (count(U.begin(), U.end(), T[i])) {
			if (isopened)cout << "Closed by "+T[i] << endl;
			else cout << "Opened by " + T[i] << endl;
			isopened = !isopened;
		}
		else
			cout << "Unknown " + T[i] << endl;
	}
	return 0;
}

C++: #include<bits/stdc++.h>
using namespace std;

int main(void){
	int n, m;
	set<string> st;
	cin >> n;
	string s;
	for(int i = 0; i < n; ++i){
		cin >> s;
		st.insert(s);
	}
	cin >> m;
	bool open = false;
	for(int i = 0; i < m; ++i){
		cin >> s;
		if(st.find(s) == st.end()){
			cout << "Unknown ";
		}else{
			if(open){
				cout << "Closed by ";
			}else{
				cout << "Opened by ";
			}
			open = !open;
		}
		cout << s << endl;
	}
	return 0;
}

C++: #pragma region
#include <bits/stdc++.h>
using namespace std;
/*
#include<ext/pb_ds/assoc_container.hpp>
#include<ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
*/
#define int long long
#define REP(i,n) for(int i = 0;i < (int)(n);i++)
#define RREP(i,n) for(int i = (int)n-1;i >= 0;i--)
#define FOR(i,s,n) for(int i = s;i < (int)n;i++)
#define RFOR(i,s,n) for(int i = (int)n-1;i >= s;i--)
#define ALL(a) a.begin(),a.end()
#define IN(a, x, b) (a<=x && x<b)
template<class T>inline bool CHMAX(T&a,T b){if(a<b){a = b;return true;}return false;}
template<class T>inline bool CHMIN(T&a,T b){if(a>b){a = b;return true;}return false;}
template<class T>istream&operator >>(istream&is,vector<T>&vec){for(T&x:vec)is>>x;return is;}
template<class T>inline void in(T&t){cin>>t;}
template<class T,class... Ts>inline void in(T&t,Ts&...ts){cin>>t;in(ts...);}
template<class T>inline void out(T t){cout<<t<<"\n";}
template<class T,class... Ts>inline void out(T t,Ts... ts){cout<<t<<" ";out(ts...);}
template<typename T=int>vector<T>mv(size_t a){return vector<T>(a);}
template<typename T=int,typename... Ts>auto mv(size_t a,Ts... ts){return vector<decltype(mv<T>(ts...))>(a,mv<T>(ts...));}
template<typename T,typename V>typename enable_if<is_class<T>::value==0>::type fill(T&t,const V&v){t=v;}
template<typename T,typename V>typename enable_if<is_class<T>::value!=0>::type fill(T&t,const V&v){for(auto &e:t)fill(e,v);}
constexpr long long INF = 1e18;
 
template<int MOD> struct Fp {
	long long val;
	constexpr Fp(long long v = 0) noexcept : val(v % MOD) {
		if (val < 0) val += MOD;
	}
	constexpr int getmod() { return MOD; }
	constexpr Fp operator - () const noexcept {
		return val ? MOD - val : 0;
	}
	constexpr Fp operator + (const Fp& r) const noexcept { return Fp(*this) += r; }
	constexpr Fp operator - (const Fp& r) const noexcept { return Fp(*this) -= r; }
	constexpr Fp operator * (const Fp& r) const noexcept { return Fp(*this) *= r; }
	constexpr Fp operator / (const Fp& r) const noexcept { return Fp(*this) /= r; }
	constexpr Fp& operator += (const Fp& r) noexcept {
		val += r.val;
		if (val >= MOD) val -= MOD;
		return *this;
	}
	constexpr Fp& operator -= (const Fp& r) noexcept {
		val -= r.val;
		if (val < 0) val += MOD;
		return *this;
	}
	constexpr Fp& operator *= (const Fp& r) noexcept {
		val = val * r.val % MOD;
		return *this;
	}
	constexpr Fp& operator /= (const Fp& r) noexcept {
		long long a = r.val, b = MOD, u = 1, v = 0;
		while (b) {
			long long t = a / b;
			a -= t * b; swap(a, b);
			u -= t * v; swap(u, v);
		}
		val = val * u % MOD;
		if (val < 0) val += MOD;
		return *this;
	}
	constexpr bool operator == (const Fp& r) const noexcept {
		return this->val == r.val;
	}
	constexpr bool operator != (const Fp& r) const noexcept {
		return this->val != r.val;
	}
	friend constexpr ostream& operator << (ostream &os, const Fp<MOD>& x) noexcept {
		return os << x.val;
	}
	friend constexpr Fp<MOD> modpow(const Fp<MOD> &a, long long n) noexcept {
		if (n == 0) return 1;
		auto t = modpow(a, n / 2);
		t = t * t;
		if (n & 1) t = t * a;
		return t;
	}
};
 
// 二項係数ライブラリ
template<class T> struct BiCoef {
	vector<T> fact_, inv_, finv_;
	constexpr BiCoef() {}
	constexpr BiCoef(int n) noexcept : fact_(n, 1), inv_(n, 1), finv_(n, 1) {
		init(n);
	}
	constexpr void init(int n) noexcept {
		fact_.assign(n, 1), inv_.assign(n, 1), finv_.assign(n, 1);
		int MOD = fact_[0].getmod();
		for(int i = 2; i < n; i++){
			fact_[i] = fact_[i-1] * i;
			inv_[i] = -inv_[MOD%i] * (MOD/i);
			finv_[i] = finv_[i-1] * inv_[i];
		}
	}
	constexpr T com(int n, int k) const noexcept {
		if (n < k || n < 0 || k < 0) return 0;
		return fact_[n] * finv_[k] * finv_[n-k];
	}
	constexpr T fact(int n) const noexcept {
		if (n < 0) return 0;
		return fact_[n];
	}
	constexpr T inv(int n) const noexcept {
		if (n < 0) return 0;
		return inv_[n];
	}
	constexpr T finv(int n) const noexcept {
		if (n < 0) return 0;
		return finv_[n];
	}
};
 
const int MOD = 1000000007;
//const int MOD = 998244353;
using mint = Fp<MOD>;
BiCoef<mint> bc;
// bc.init(500050);
int A,B,C,D,E,F,G,H,I,J,K,L,M,N,O,P,Q,R,S,T,U,V,W,X,Y,Z;
#pragma endregion

#define endl '\n'
#define IOS() ios_base::sync_with_stdio(0);cin.tie(0)

signed main(){
	IOS();
	in(N);
	map<string,int>mp;
	REP(i,N){
		string s;
		in(s);
		mp[s]=0;
	}
	in(M);
	int flg = 0;
	REP(i,M){
		string s;
		in(s);
		if(!mp.count(s))out("Unknown",s);
		else{
			if(flg==0){
				out("Opened by",s);
			}else{
				out("Closed by",s);
			}
			flg^=1;
		}
	}
}

C++: #define _CRT_SECURE_NO_WARNINGS
#include <iostream>
#include <cstdio>
#include <vector>
#include <string>
#include <array>
#include <queue>
#include <deque>
#include <set>
#include <list>
#include <map>
#include <stack>
#include <utility>
#include <algorithm>
#include <numeric>
#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <cctype>
#include <cstring>
#include <climits>
#include <bitset>
#include <random>
#include <functional>
#include <sstream>
#include <iomanip>

using namespace std;

#define rep(i, n) for(int i=0; i<(n); i++)
#define FOR(i, m, n) for(int i=(m);i<(n);i++)
#define sz(x) ((int)(x).size())
#define all(x) (x).begin(),(x).end()
#define SORT(x) sort((x).begin(),(x).end())
#define REVE(x) reverse((x).begin(),(x).end())
#define mp make_pair
#define pb push_back

typedef vector<int> VI;
typedef vector<string> VS;
typedef vector<vector<int>> VVI;
typedef pair<int, int> PII;
typedef long long LL;

int main() {
	int n; cin >> n;
	VS u(n);
	rep(i, n)cin >> u[i];

	bool open = false;
	int m; cin >> m;
	rep(i, m) {
		string t;
		cin >> t;

		auto re = find(all(u), t);
		if (re == u.end()) {
			cout << "Unknown " << t << endl;
		}
		else {
			if (!open)open = true, cout << "Opened by " << t << endl;
			else open = false, cout << "Closed by " << t << endl;
		}
	}
}