#include <bits/stdc++.h>
using namespace std;
const int inf = 1e6;
int n;
int x[1005], y[1005];
int main(void) {
  ios_base::sync_with_stdio(0);
  cin.tie(NULL);
  cin >> n;
  for (int i = 1; i <= n; ++i) cin >> x[i] >> y[i], x[i] += inf, y[i] += inf;
  while (true) {
    int c1 = 0, c2 = 0;
    for (int i = 1; i <= n; ++i) {
      if ((x[i] + y[i]) % 2 == 0)
        ++c1;
      else
        ++c2;
    }
    if (c1 && c2) {
      vector<int> ans;
      for (int i = 1; i <= n; ++i)
        if ((x[i] + y[i]) % 2 == 0) ans.push_back(i);
      cout << ans.size() << endl;
      for (auto f : ans) cout << f << ' ';
      cout << endl;
      return 0;
    }
    int mn = 0;
    for (int i = 1; i <= n; ++i) {
      int f = x[i] + y[i], g = x[i] - y[i];
      if (f & 1) ++f, ++g;
      x[i] = f / 2, y[i] = g / 2;
      mn = min(mn, y[i]);
    }
    for (int i = 1; i <= n; ++i) y[i] -= mn;
  }
  return 0;
}
