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

int main() {
  int n,m;cin>>n>>m;
  vector<int> l(m);
  vector<int> r(m);
  for(int i=0;i<m;i++){
    cin>>l[i]>>r[i];
    if(l[i]==n)n=r[i];
    else if(r[i]==n)n=l[i];
  }
  cout<<n<<endl;
  return 0;
}