#include <iostream>
#include <vector>
#include <algorithm>
#include <string>
#include <map>
#include <queue>
#include <numeric>
#include <climits>
using namespace std;
using ll = long long;
const ll mod = 1000000007;
int n, m;
string s, t;
int main() {
	cin.tie(0);
	ios::sync_with_stdio(false);
	cin >> n >> m;
	int pos = n;
	int num[4] = {0, 1, 2, 3 };
	while (m > 0) {
		int a, b; cin >> a >> b;
		if (pos == a) {
			pos = b;
		}
		else if (pos == b) {
			pos = a;
		}
		
		m--;
	}
	cout << pos << endl;
	return 0;
}