#include <iostream>
#include <vector>
#include <algorithm>
#include <cmath>
#include <iomanip>
#include <stack>
#include <algorithm>
#include <string>
#include <map>
#include <iterator>
#include <set>
#include <queue>

using namespace std;

int main() {


    int N, M;
    cin >> N >> M;
    for (int i = 0; i < M; ++i) {
        int P, Q;
        cin >> P >> Q;

        if (N == P) {
            N = Q;
        } else if (N == Q) {
            N = P;
        }
    }

    cout << N << endl;

    return 0;

}