#include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include template inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; } template inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; } //constexpr long long MAX = 5100000; constexpr long long INF = 1LL << 60; constexpr int inf = 1000000007; //constexpr long long mod = 1000000007LL; constexpr long long mod = 998244353LL; const long double PI = acos((long double)(-1)); using namespace std; typedef unsigned long long ull; typedef long long ll; typedef long double ld; mt19937 rnd(chrono::steady_clock::now().time_since_epoch().count()); int d(int x1, int y1, int x2, int y2) { return (x1 - x2) * (x1 - x2) + (y1 - y2) * (y1 - y2); } int main() { /* cin.tie(nullptr); ios::sync_with_stdio(false); */ int n; scanf("%d", &n); int k = (n + 89) / 90; vector x(n), y(n); for (int i = 0; i < n; i++) scanf("%d %d", &x[i], &y[i]); int idx = min_element(x.begin(), x.end()) - x.begin(); for (int i = 0; i < n; i++) { if (x[i] == x[idx] and y[i] < y[idx]) { idx = i; } } vector v; for (int i = 0; i < n; i++) if (i != idx) v.emplace_back(i); sort(v.begin(), v.end(), [&](int i, int j) {return d(x[idx], y[idx], x[i], y[i]) < d(x[idx], y[idx], x[j], y[j]); }); reverse(v.begin(), v.end()); vector res; res.emplace_back(idx); while (res.size() < k) { if (v.empty()){ assert(false); } int p = v.back(); v.pop_back(); bool ok = true; for (auto e : res) { int len2 = (x[e] - x[p]) * (x[e] - x[p]) + (y[e] - y[p]) * (y[e] - y[p]); if (len2 < 100) { ok = false; break; } } if (ok) res.emplace_back(p); } cout << res.size() << "\n"; for (int i = 0; i < res.size(); i++) cout << res[i] + 1<< " \n"[i + 1 == res.size()]; return 0; }