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


int main() {
	int N, M;
	cin >> N >> M;
	vector<int> P(M), Q(M);
	for(int i=0; i<M; i++) cin >> P[i] >> Q[i];

	for (int i = 0; i < M; i++) {
		if (P[i] == N) {
			N = Q[i];
		}
		else if (Q[i] == N) {
			N = P[i];
		}
	}

	cout << N << endl;

}