#include <iostream>
using namespace std;

int main(){
  int n, m;

  while(cin >> n >> m){
    for(int i = 0; i < m; i++){
      int a, b;
      cin >> a >> b;

      if(a == n){
        n = b;
      }
      else if(b == n){
        n = a;
      }
    }

    cout << n << endl;
  }
}