#include<iostream>
#include<algorithm>
#include<stdio.h>
#include<stdlib.h>
#include<vector>
#include<string>
#include<sstream>
#include<math.h>
using namespace std;


int main(){

  int n, m;
  cin >> n;
  cin >> m;

  vector<int> a(m);
  vector<int> b(m);
  for(int i=0;i<m;i++) cin >> a[i] >> b[i];

  for(int i=0; i<m; i++){
    if( n == a[i] ) n = b[i];
    else if( n == b[i] ) n = a[i];
  }
  cout << n << endl;

  return 0;
}