#include<iostream>
#include<string>
#include<string.h>
#include<algorithm>
#include<stdio.h>
#include<cmath>
#include<vector>
#include<utility>
#include<stack>
#include<queue>
#include<list>
#include<bitset>

#define FOR(i, a, b) for(int i=(a);i<=(b);i++)
#define RFOR(i, a, b) for(int i=(a);i>=(b);i--)
#define MOD 1000000007
#define INF 1000000000

using namespace std;


int main(void) {
	int n, m;

	cin >> n >> m;

	FOR(i, 1, m) {
		int p, q;
		cin >> p >> q;
		if (n == p) {
			n = q;
		}
		else if (n == q) {
			n = p;
		}
	}
	cout << n << endl;
	return 0;
}