#include // {{{ // https://codeforces.com/blog/entry/96344 #pragma GCC optimize("O2,unroll-loops") #pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt") using namespace std; template [[nodiscard]] static T MIN() { return std::numeric_limits::min(); } template [[nodiscard]] static T MAX() { return std::numeric_limits::max(); } template [[nodiscard]] static T sc(auto &&x) { return static_cast(x); } template [[nodiscard]] static T sz(auto &&x) { return static_cast(x.size()); } #define prln(...) std::println(__VA_ARGS__) #define pr(...) std::print(__VA_ARGS__) #ifdef LOCAL #define dbgln(...) std::println(__VA_ARGS__) #define dbg(...) std::print(__VA_ARGS__) #endif inline static void NO() { prln("NO"); } inline static void YES() { prln("YES"); } using ll = long long; using ld = long double; template using ve = std::vector; template using ar = std::array; template using pa = std::pair; template using tu = std::tuple; template using dq = std::deque; template using qu = std::queue; template using pq = std::priority_queue; template using st = std::stack; auto lb = [](auto... args) { return std::lower_bound(args...); }; auto ub = [](auto... args) { return std::upper_bound(args...); }; #define ff first #define ss second #define eb emplace_back #define pb push_back #define all(x) (x).begin(), (x).end() #define rall(x) (x).rbegin(), (x).rend() // }}} #include #include using namespace __gnu_pbds; // https://mirror.codeforces.com/blog/entry/124683 namespace hashing { using i64 = std::int64_t; using u64 = std::uint64_t; static const u64 FIXED_RANDOM = std::chrono::steady_clock::now().time_since_epoch().count(); #if USE_AES std::mt19937 rd(FIXED_RANDOM); const __m128i KEY1{(i64)rd(), (i64)rd()}; const __m128i KEY2{(i64)rd(), (i64)rd()}; #endif template struct custom_hash {}; template inline void hash_combine(u64 &seed, T const &v) { custom_hash hasher; seed ^= hasher(v) + 0x9e3779b97f4a7c15 + (seed << 12) + (seed >> 4); }; template struct custom_hash::value>::type> { u64 operator()(T _x) const { u64 x = _x; #if USE_AES __m128i m{i64(u64(x) * 0xbf58476d1ce4e5b9u64), (i64)FIXED_RANDOM}; __m128i y = _mm_aesenc_si128(m, KEY1); __m128i z = _mm_aesenc_si128(y, KEY2); return z[0]; #else x += 0x9e3779b97f4a7c15 + FIXED_RANDOM; x = (x ^ (x >> 30)) * 0xbf58476d1ce4e5b9; x = (x ^ (x >> 27)) * 0x94d049bb133111eb; return x ^ (x >> 31); #endif } }; template struct custom_hash()))>> { u64 operator()(T const &a) const { u64 value = FIXED_RANDOM; for (auto &x : a) hash_combine(value, x); return value; } }; template struct custom_hash> { u64 operator()(const std::tuple &a) const { u64 value = FIXED_RANDOM; std::apply( [&value](T const &...args) { (hash_combine(value, args), ...); }, a); return value; } }; template struct custom_hash> { u64 operator()(std::pair const &a) const { u64 value = FIXED_RANDOM; hash_combine(value, a.first); hash_combine(value, a.second); return value; } }; }; // namespace hashing #ifdef PB_DS_ASSOC_CNTNR_HPP template using hashtable = gp_hash_table< Key, Value, hashing::custom_hash, std::equal_to, direct_mask_range_hashing<>, linear_probe_fn<>, hash_standard_resize_policy, hash_load_check_resize_trigger<>, true>>; #endif #ifdef PB_DS_TREE_POLICY_HPP template using multitree = tree, rb_tree_tag, tree_order_statistics_node_update>; template using rbtree = tree, rb_tree_tag, tree_order_statistics_node_update>; #endif void solve() { int n; cin >> n; // NOTE: keep forgetting to initialize vector with size // NOTE: thought could just use angles -> completely wrong ve> points(n); map xs, ys; for (int i = 0; i < n; ++i) { cin >> points[i].ff >> points[i].ss; ++xs[points[i].ff]; ++ys[points[i].ss]; } ll ans = 0; for (auto [_, f] : xs) { ans += f * (f - 1) / 2; } for (auto [_, f] : ys) { ans += f * (f - 1) / 2; } xs.clear(); ys.clear(); // NOTE: claude did tihs, to account for precision errors, no idea why this // works for (auto [x, y] : points) { ll rx = x + y; ll ry = x - y; ++xs[rx]; ++ys[ry]; } for (auto [_, f] : xs) { ans += f * (f - 1) / 2; } for (auto [_, f] : ys) { ans += f * (f - 1) / 2; } prln("{}", ans * 2); // WRONG: // for the fun of it, let's change this up - find the angle each point makes // with 0 then should be same counting approach // should be: count all points with same y value, n * (n - 1) / 2 // and same x // then rotate 45 degrees, do the same- guaranteed no overcounting // PAUSED AT 17:00 } int main() { // {{{ cin.tie(nullptr)->sync_with_stdio(false); cin.exceptions(cin.failbit); int t = 1; cin >> t; while (t--) { solve(); } return 0; } // }}}