#include <bits/stdc++.h>
using namespace std;

int main() {
  int N, M;
  cin >> N >> M;
  for (int i = 0, p, q; i < M && cin >> p >> q; i++) {
    if (N == p) N = q;
    else if (N == q) N = p;
  }
  cout << N << "\n";
}