#include <bits/stdc++.h>

using ull = unsigned long long;
const int N = 1e6 + 10;

std::mt19937_64 rng(41);
std::string oper;

ull a[N], xsum, xid;

int n;
void Anya(){
	std::cin >> n;
	for(int i = 1, x; i <= n; ++i){
		std::cin >> x;
		xsum ^= a[x], xid ^= x;
		if(!xsum && !xid) std::cout << "0\n";
		else if(xid < N & a[xid] == xsum) std::cout << xid << '\n';
		else std::cout << "-1\n";
	}
	std::cout << xsum << " " << xid << '\n';
}

void Andrei(){
	std::cin >> xsum >> xid;
	std::cin >> n;
	for(int i = 1, x; i <= n; ++i){
		std::cin >> x;
		xsum ^= a[x], xid ^= x;
		if(!xsum && !xid) std::cout << "0\n";
		else if(xid < N & a[xid] == xsum) std::cout << xid << '\n';
		else std::cout << "-1\n";
	}
}

int main(){
	std::ios::sync_with_stdio(false);
	std::cin >> oper;
	for(int i = 1; i < N; ++i) a[i] = rng();
	if(oper == "start") Anya();
	else Andrei();
	return 0;
}