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

int main(){
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
 
    int p,Q; cin >> p >> Q;
    while(Q--){
        int a,b; cin >> a >> b;
        if(p == a) p = b;
        else if(p == b) p = a;
    }
    cout << p << endl;
}