#include <bits/stdc++.h>
using namespace std;

int main() {
  int N, M;
  cin >> N;
  cin >> M;
  vector<int> a = {1,2,3};
  for (int i = 0; i < M; i++) {
    int P, Q;
    cin >> P >> Q;
    P--;
    Q--;
    a[P] ^= a[Q] ^= a[P] ^= a[Q];
  }
  for (int i = 0; i < 3; i++) {
    if (a[i] == M) {
      i++;
      printf("%d\n", i);
      break;
    }
  }
  return 0;
}