#include <algorithm>
#include <iostream>
#include <cstdio>
#include <map>
#include <numeric>
#include <cmath>
#include <set>
#include <sstream>
#include <string>
#include <vector>
#include <queue>
#include <complex>
#include <string.h>
#include <unordered_set>
#include <unordered_map>
using namespace std;

#define endl '\n'
#define all(v) (v).begin(), (v).end()
#define rall(v) (v).rbegin(), (v).rend()
#define uniq(v) (v).erase(unique((v).begin(), (v).end()), (v).end())

typedef long long ll;
typedef pair<int, int> P;
typedef unsigned int uint;
typedef unsigned long long ull;
struct pairhash {
public:
    template<typename T, typename U>
    size_t operator()(const pair<T, U> &x) const {
	size_t seed = hash<T>()(x.first);
	return hash<U>()(x.second) + 0x9e3779b9 + (seed<<6) + (seed>>2);
    }
};

const int inf = 1000000009;

int main() {
    int n, m;
    scanf("%d%d", &n, &m);
    for (int i = 0; i < m; i++) {
	int p, q;
	scanf("%d%d", &p, &q);
	if (n == p) {
	    n = q;
	} else if (n == q) {
	    n = p;
	}
    }
    printf("%d\n", n);
}