#include <iostream>
#include <list>
#include <vector>
#include <string>
#include <stdio.h>
#include <stdint.h>
using namespace std;

using uint = unsigned int;
using ll = long long;

int main()
{

  ll N;
  ll M;
  cin >> N;
  cin >> M;
  ll P;
  ll Q;

  for( ll i = 0 ; i < M ; i++ ){

    cin >> P;
    cin >> Q;

    if( N == P ){

      N = Q;

    } else if( N == Q ) {

      N = P;
      
    }

  }

  cout << N << endl;
  return 0;

}