結果

問題 No.2510 Six Cube Sum Counting
ユーザー sten_sansten_san
提出日時 2023-10-21 00:54:23
言語 C++17(gcc12)
(gcc 12.3.0 + boost 1.87.0)
結果
AC  
実行時間 1,157 ms / 4,000 ms
コード長 3,386 bytes
コンパイル時間 4,314 ms
コンパイル使用メモリ 237,084 KB
実行使用メモリ 340,644 KB
最終ジャッジ日時 2024-09-21 01:39:07
合計ジャッジ時間 27,013 ms
ジャッジサーバーID
（参考情報） 		judge5 / judge1
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ファイルパターン 結果
sample AC * 4
other AC * 26
権限があれば一括ダウンロードができます

ソースコード

diff # 

#include <bits/stdc++.h>
using namespace std;

struct iofast_t {
    iofast_t() {
        ios::sync_with_stdio(false);
        cin.tie(nullptr);
    }
} iofast;

struct uns_t {} uns;
template <typename Element, typename Head, typename ...Args>
auto vec(Element init, Head arg, Args ...args) {
    if constexpr (sizeof...(Args) == 0) return vector(arg, init);
    else return vector(arg, vec(init, args...));
}
template <typename Element, typename Head, typename ...Args>
auto vec(uns_t, Head arg, Args ...args) {
    return vec(Element(), arg, args...);
}

template <typename Container>
auto distance(const Container &c, decltype(begin(c)) iter) {
    return distance(begin(c), iter);
}

template <typename RIter, typename Compare = less<typename iterator_traits<RIter>::value_type>>
auto isort(RIter first, RIter last, Compare comp = Compare()) {
    vector<int> i(distance(first, last));
    iota(begin(i), end(i), 0);
    sort(begin(i), end(i), [&](auto x, auto y) {
        return comp(*(first + x), *(first + y));
    });
    return i;
}

template <typename, template <typename> typename, typename = void_t<>>
struct detect : false_type {};
template <typename T, template <typename> typename Check>
struct detect<T, Check, void_t<Check<T>>> : true_type {};
template <typename T, template <typename> typename Check>
constexpr inline bool detect_v = detect<T, Check>::value;

template <typename T>
using has_member_sort = decltype(declval<T>().sort());

template <typename Container, typename Compare = less<typename Container::value_type>>
auto sorted(Container c, Compare comp = Compare()) {
    if constexpr (detect_v<Container, has_member_sort>) {
        c.sort(comp);
        return c;
    }
    else {
        sort(begin(c), end(c), comp);
        return c;
    }
}

template <typename Container, typename Compare = equal_to<typename Container::value_type>>
auto uniqued(Container c, Compare comp = Compare()) {
    c.erase(unique(begin(c), end(c), comp), end(c));
    return c;
}

template <typename T, typename Compare = less<T>>
T &chmin(T &l, T r, Compare &&f = less<T>()) { return l = min(l, r, f); }
template <typename T, typename Compare = less<T>>
T &chmax(T &l, T r, Compare &&f = less<T>()) { return l = max(l, r, f); }

template <typename F>
constexpr auto fix(F &&f) noexcept {
    return [f = std::tuple<F>(std::forward<F>(f))](auto &&...args) mutable {
        return std::get<0>(f)(fix(std::get<0>(f)), std::forward<decltype(args)>(args)...);
    };
}

#include <ext/pb_ds/assoc_container.hpp>

int main() {
    int x; cin >> x;

    int lim = 0;
    while (lim <= 300 && lim * lim * lim <= x) {
        ++lim;
    }

    auto l = vec<int>(uns, lim, 0);
    auto r = vec<int>(uns, lim, 0);

    fix([&](auto f, int first, int last, int acc = 0, int d = 0) -> void {
        if (3 <= d) {
            l[first].push_back(acc);
            r[last].push_back(acc);
            return;
        }

        while (last <= 300 && acc + last * last * last <= x) {
            f(d != 0 ? first : last, last, acc + last * last * last, d + 1);
            ++last;
        }
    })(0, 0);

    __gnu_pbds::gp_hash_table<int, int> count;

    int64_t ans = 0;

    for (int i = lim - 1; 0 <= i; --i) {
        for (auto v : l[i]) {
            ++count[v];
        }

        for (auto v : r[i]) {
            ans += count[x - v];
        }
    }

    cout << ans << endl;
}
0