#include <bits/stdc++.h>
struct MI {
 private:
  char bb[1 << 14];
  FILE *f;
  char *bs, *be;
  char e;
  bool o, l;

 public:
  MI() : f(stdin), bs(0), be(0) {}
  MI(FILE *f) : f(f), bs(0), be(0) {}
  inline operator bool() { return !l; }
  inline char get() {
    if (o) {
      o = 0;
      return e;
    }
    if (bs == be) be = (bs = bb) + fread(bb, 1, sizeof(bb), f);
    if (bs == be) {
      l = 1;
      return -1;
    };
    return *bs++;
  }
  inline void unget(char c) {
    o = 1;
    e = c;
  }
  template <class T>
  inline T read() {
    T r;
    *this > r;
    return r;
  }
  template <class T>
  inline MI &operator>(T &);
};
template <class T>
struct Q {
  const static bool U = T(-1) >= T(0);
  inline void operator()(MI &t, T &r) const {
    r = 0;
    char c;
    bool y = 0;
    if (U)
      for (;;) {
        c = t.get();
        if (c == -1) goto E;
        if (isdigit(c)) break;
      }
    else
      for (;;) {
        c = t.get();
        if (c == -1) goto E;
        if (c == '-') {
          c = t.get();
          if (isdigit(c)) {
            y = 1;
            break;
          };
        } else if (isdigit(c))
          break;
        ;
      };
    for (;;) {
      if (c == -1) goto E;
      if (isdigit(c))
        r = r * 10 + (c ^ 48);
      else
        break;
      c = t.get();
    }
    t.unget(c);
  E:;
    if (y) r = -r;
  }
};
template <>
struct Q<char> {
  inline void operator()(MI &t, char &r) {
    int c;
    for (;;) {
      c = t.get();
      if (c == -1) {
        r = -1;
        return;
      };
      if (!isspace(c)) {
        r = c;
        return;
      };
    }
  }
};
template <class T>
inline MI &MI::operator>(T &t) {
  Q<T>()(*this, t);
  return *this;
}
template <class T>
std::ostream &operator<(std::ostream &out, const T &t) {
  return out << t;
}
using std::cout;
MI cin;
const int $n = 1005;
template <typename T>
inline bool gmin(T &a, const T &b) {
  return b < a && (a = b, true);
}
template <typename T>
inline bool gmax(T &a, const T &b) {
  return a < b && (a = b, true);
}
int n, c[2][2];
struct point {
  int x, y;
} v[$n];
int main() {
  cin > n;
  for (int __r = (n), i = (1); i <= __r; ++i) cin > v[i].x > v[i].y;
  for (;;) {
    memset(c, 0, sizeof(c));
    for (int __r = (n), i = (1); i <= __r; ++i) ++c[v[i].x & 1][v[i].y & 1];
    if ((c[0][1] || c[1][0]) && (c[0][0] || c[1][1])) {
      int ans = c[0][1] + c[1][0];
      cout < ans < ('\n');
      for (int __r = (n), i = (1); i <= __r; ++i)
        if ((v[i].x ^ v[i].y) & 1) cout < i < " \n"[!--ans];
      return 0;
    }
    if (c[0][1] && c[1][0]) {
      int ans = c[0][1];
      cout < ans < ('\n');
      for (int __r = (n), i = (1); i <= __r; ++i)
        if (!(v[i].x & 1) && (v[i].y & 1)) cout < i < " \n"[!--ans];
      return 0;
    }
    if (c[0][0] && c[1][1]) {
      int ans = c[0][0];
      cout < ans < ('\n');
      for (int __r = (n), i = (1); i <= __r; ++i)
        if (!(v[i].x & 1) && !(v[i].y & 1)) cout < i < " \n"[!--ans];
      return 0;
    }
    for (int __r = (n), i = (1); i <= __r; ++i) v[i].x >>= 1, v[i].y >>= 1;
  }
}
