#include <bits/stdc++.h>
#pragma GCC optimize("Ofast")
#pragma GCC target("avx,avx2")
using namespace std;
ostream &operator<<(ostream &out, string str) {
  for (char c : str) out << c;
  return out;
}
template <class L, class R>
ostream &operator<<(ostream &out, pair<L, R> p) {
  return out << "(" << p.first << ", " << p.second << ")";
}
template <class T>
auto operator<<(ostream &out, T a) -> decltype(a.begin(), out) {
  out << "{";
  for (auto it = a.begin(); it != a.end(); it = next(it))
    out << (it != a.begin() ? ", " : "") << *it;
  return out << "}";
}
void dump() { cerr << "\n"; }
template <class T, class... Ts>
void dump(T a, Ts... x) {
  cerr << a << ", ";
  dump(x...);
}
template <class T>
int size(T &&a) {
  return a.size();
}
using LL = long long;
using PII = pair<int, int>;
mt19937 rng(chrono::system_clock::now().time_since_epoch().count());
int rd(int a, int b) { return uniform_int_distribution<int>(a, b)(rng); }
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  int n;
  cin >> n;
  vector<int> x(n), y(n);
  for (int i = 0; i < n; i++) cin >> x[i] >> y[i];
  vector<LL> w;
  vector<vector<PII>> e;
  map<LL, int> S;
  map<LL, bool> used;
  for (int i = 0; i < n; i++)
    for (int j = 0; j < n; j++) {
      LL _x = x[i] - x[j];
      LL _y = y[i] - y[j];
      LL d = _x * _x + _y * _y;
      if (S.find(d) == S.end()) {
        S[d] = size(e);
        e.emplace_back();
      }
      int id = S[d];
      e[id].emplace_back(i, j);
      w.emplace_back(d);
    }
  while (true) {
    LL x = w[rd(0, size(w) - 1)];
    while (used[x]) {
      x = w[rd(0, size(w) - 1)];
    }
    used[x] = true;
    vector<vector<int>> graph(n);
    int id = S[x];
    for (PII p : e[id]) {
      int i, j;
      tie(i, j) = p;
      graph[i].emplace_back(j);
      graph[j].emplace_back(i);
    }
    vector<int> col(n, -1);
    bool good = true;
    for (int i = 0; i < n; i++) {
      if (col[i] == -1) {
        vector<int> Q = {i};
        col[i] = 0;
        while (!Q.empty()) {
          int v = Q.back();
          Q.pop_back();
          for (int u : graph[v]) {
            if (col[u] == -1) {
              col[u] = col[v] ^ 1;
              Q.emplace_back(u);
            } else if (col[u] == col[v]) {
              good = false;
              break;
            }
          }
          if (!good) break;
        }
      }
      if (!good) break;
    }
    if (!good) continue;
    for (auto &v : e) {
      int q = -1;
      for (PII p : v) {
        int x = col[p.first] ^ col[p.second];
        if (q == -1) q = x;
        if (q != x) {
          good = false;
          break;
        }
      }
      if (!good) break;
    }
    if (!good) continue;
    int cnt = 0;
    for (int i = 0; i < n; i++)
      if (col[i]) cnt++;
    cout << cnt << "\n";
    for (int i = 0; i < n; i++)
      if (col[i]) cout << i + 1 << " ";
    cout << "\n";
    return 0;
  }
}
