#include<iostream>
#include<string>
#include<algorithm>
#include<cctype>
#include<set>
#include<bitset>
#include<math.h>
#include<map>
#include<queue>
#include<iomanip>
using namespace std;

int main(){
    int y, m;
    cin >> y >> m;
    for (int i = 0; i < m; i++){
        int a, b;
        cin >> a >> b;
        if (a == y) y = b;
        else if (b == y) y = a;
    }
    cout << y << endl;
}