#include<iostream>
#include<map>
using namespace std;
int main() {
	int n, m; cin >> n >> m;
	for (int i = 0; i < m; i++) {
		int a, b; cin >> a >> b;
		if (a == n)n = b;
		else if (b == n)n = a;
	}
	cout << n << endl;
}