#include <iostream>
#include <vector>

int main() {
    using namespace std;
    int n, m;
    cin >> n >> m;
    while (m--) {
        int p, q;
        cin >> p >> q;
        if (p == n) {
            n = q;
        } else if (q == n) {
            n = p;
        }
    }
    cout << n << endl;
}