#include <iostream>
#include <algorithm>
#include <vector>
using namespace std;

int main(){
	int N, M;
	cin >> N;
	cin >> M;
	for (int i = 0; i < M; i++){
		int p, q; cin >> p >> q;
		if (N == p) N = q;
		else if (N == q) N = p;
	}
	cout << N << endl;
	return 0;
}