#include <bits/stdc++.h>
using namespace std;
template <class T>
inline bool chmax(T& a, T b) {
  if (a < b) {
    a = b;
    return true;
  }
  return false;
}
template <class T>
inline bool chmin(T& a, T b) {
  if (a > b) {
    a = b;
    return true;
  }
  return false;
}
int dx[4] = {1, 0, -1, 0};
int dy[4] = {0, 1, 0, -1};
const long long INF = 1LL << 60;
const long long mod = (int)1e9 + 7;
int main() {
  int n;
  cin >> n;
  if (n == 2) {
    cout << 1 << endl;
    cout << 1;
    return 0;
  }
  vector<pair<int, int> > v(n);
  for (int i = 0; i < n; i++) {
    int x, y;
    cin >> x >> y;
    v[i] = make_pair(x, y);
  }
  while (true) {
    vector<int> a;
    vector<int> c;
    vector<int> e;
    for (int i = 0; i < n; i++) {
      if ((v[i].first + v[i].second) % 2) a.push_back(i);
      if (v[i].first % 2) c.push_back(i);
      if (v[i].second % 2) e.push_back(i);
    }
    if (((long long)(a).size()) == 0 || ((long long)(a).size()) == n) {
      if (((long long)(c).size()) == 0 || ((long long)(c).size()) == n) {
        if (((long long)(e).size()) == 0 || ((long long)(e).size()) == n) {
          for (int i = 0; i < n; i++) {
            v[i].first = (v[i].first - abs(v[i].first) % 2) / 2;
            v[i].second = (v[i].second - abs(v[i].second) % 2) / 2;
          }
        } else {
          cout << ((long long)(e).size()) << endl;
          for (auto x : e) cout << x + 1 << ' ';
          return 0;
        }
      } else {
        cout << ((long long)(c).size()) << endl;
        for (auto x : c) cout << x + 1 << ' ';
        return 0;
      }
    } else {
      cout << ((long long)(a).size()) << endl;
      for (auto x : a) cout << x + 1 << ' ';
      return 0;
    }
  }
}
