895

codeforces/871/g.cc

@@ -0,0 +1,124 @@
+#include <bits/stdc++.h>  // {{{
+
+// https://codeforces.com/blog/entry/96344
+
+#pragma GCC optimize("O2,unroll-loops")
+#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
+
+using namespace std;
+
+template <typename T>
+[[nodiscard]] static T MIN() {
+  return std::numeric_limits<T>::min();
+}
+
+template <typename T>
+[[nodiscard]] static T MAX() {
+  return std::numeric_limits<T>::max();
+}
+
+template <typename T>
+[[nodiscard]] static T sc(auto&& x) {
+  return static_cast<T>(x);
+}
+
+template <typename T>
+[[nodiscard]] static T sz(auto&& x) {
+  return static_cast<T>(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 <typename T>
+using ve = std::vector<T>;
+template <typename T, size_t N>
+using ar = std::array<T, N>;
+template <typename T1, typename T2>
+using pa = std::pair<T1, T2>;
+template <typename... Ts>
+using tu = std::tuple<Ts...>;
+template <typename... Ts>
+using dq = std::deque<Ts...>;
+template <typename... Ts>
+using qu = std::queue<Ts...>;
+template <typename... Ts>
+using pq = std::priority_queue<Ts...>;
+template <typename... Ts>
+using st = std::stack<Ts...>;
+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()
+//  }}}
+
+void solve() {
+  int n;
+  cin >> n;
+  ll l = 1, r = 1e6;
+  while (l <= r) {
+    ll m = l + (r - l) / 2;
+    if (m * (m + 1) / 2 >= n) {
+      r = m - 1;
+    } else {
+      l = m + 1;
+    }
+  }
+  auto sumsq = [](ll x) {
+    return x * (x + 1) * (2 * x + 1) / 6;
+  };
+  ll level = l;
+  ll ans = 0;
+  l = r = level - (level * (level + 1) / 2 - n) - 1;
+  while (level > 0) {
+    l = max(0LL, l);
+    r = min(r, level - 1);
+
+    auto left = level * (level + 1) / 2 - level + 1;
+    ans -= sumsq(left + l - 1);
+    ans += sumsq(left + r);
+
+    --l;
+    --level;
+  }
+  prln("{}", ans);
+}
+
+int main() {  // {{{
+  cin.tie(nullptr)->sync_with_stdio(false);
+  cin.exceptions(cin.failbit);
+
+  int t = 1;
+  cin >> t;
+
+  while (t--) {
+    solve();
+  }
+
+  return 0;
+}
+// }}}