#include <iostream>
using namespace std;

int main(void){
  int n,m,p,q;
  
  cin >> m >> n;
  for (int i=0; i<n; i++){
    cin >> p >> q;
    if (m==p) m=q;
    else if (m==q) m=p;
  }
  cout << m << endl;
  return 0;
}