//Normal

#define _GLIBCXX_DEBUG
#define ll long long
#include <bits/stdc++.h>
using namespace std;
using Graph = vector<vector<int>>;

void print(auto a){
  cout << a;
}

void prints(auto a){
  cout << a << " ";
}

void prints(){
  cout << " ";
}

void printl(auto a){
  cout << a << endl;
}

void printl(){
  cout << endl;
}

void fix(int n){
  cout << fixed << setprecision(n);
}

int siz(string s){
  return (int)s.size();
}

int main(){
  int N, M; cin >> N >> M;
  
  for(int i = 0; i < M; i++){
    int A, B; cin >> A >> B;
    
    if(N == A or N == B) N == A ? N = B : N = A;
  }
  
  printl(N);
  return 0;
}