#include <iostream>

#define SWAP(a,b) (a ^= b,b = a ^ b,a ^= b)

using namespace std;

int main()
{
	int N, M, P, Q, c[4] = { 0 };
	cin >> N >> M;

	c[N] = 1;
	for (int i = 0; i < M; i++) {
		cin >> P >> Q;
		SWAP(c[P], c[Q]);
	}
	cout << (c[1] ? 1 : (c[2] ? 2 : 3)) << endl;

	return 0;
}