結果

問題 No.1683 Robot Guidance
ユーザー KoDKoD
提出日時 2021-09-17 21:53:16
言語 C++23
(gcc 12.3.0 + boost 1.83.0)
結果
AC  
実行時間 58 ms / 2,000 ms
コード長 7,023 bytes
コンパイル時間 2,575 ms
コンパイル使用メモリ 252,332 KB
実行使用メモリ 19,660 KB
最終ジャッジ日時 2024-06-29 20:19:48
合計ジャッジ時間 4,371 ms
ジャッジサーバーID
(参考情報)
judge5 / judge2
このコードへのチャレンジ
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テストケース

テストケース表示
入力 結果 実行時間
実行使用メモリ
testcase_00 AC 2 ms
5,248 KB
testcase_01 AC 2 ms
5,376 KB
testcase_02 AC 2 ms
5,376 KB
testcase_03 AC 10 ms
5,900 KB
testcase_04 AC 4 ms
5,376 KB
testcase_05 AC 7 ms
5,376 KB
testcase_06 AC 14 ms
5,860 KB
testcase_07 AC 11 ms
5,860 KB
testcase_08 AC 45 ms
12,612 KB
testcase_09 AC 16 ms
6,888 KB
testcase_10 AC 35 ms
11,496 KB
testcase_11 AC 32 ms
11,376 KB
testcase_12 AC 46 ms
13,536 KB
testcase_13 AC 2 ms
5,376 KB
testcase_14 AC 58 ms
19,660 KB
testcase_15 AC 41 ms
15,748 KB
testcase_16 AC 3 ms
5,376 KB
testcase_17 AC 2 ms
5,376 KB
testcase_18 AC 2 ms
5,376 KB
testcase_19 AC 2 ms
5,376 KB
testcase_20 AC 2 ms
5,376 KB
testcase_21 AC 2 ms
5,376 KB
testcase_22 AC 11 ms
6,500 KB
testcase_23 AC 40 ms
15,556 KB
testcase_24 AC 45 ms
12,312 KB
testcase_25 AC 40 ms
15,592 KB
testcase_26 AC 3 ms
5,376 KB
testcase_27 AC 25 ms
11,576 KB
testcase_28 AC 40 ms
15,588 KB
testcase_29 AC 2 ms
5,376 KB
testcase_30 AC 39 ms
15,588 KB
testcase_31 AC 12 ms
6,372 KB
testcase_32 AC 43 ms
16,744 KB
testcase_33 AC 25 ms
9,576 KB
testcase_34 AC 26 ms
9,408 KB
testcase_35 AC 44 ms
16,104 KB
testcase_36 AC 45 ms
16,104 KB
testcase_37 AC 8 ms
5,376 KB
testcase_38 AC 42 ms
16,052 KB
testcase_39 AC 22 ms
9,448 KB
testcase_40 AC 1 ms
5,376 KB
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 i32 = std::int32_t;
using u32 = std::uint32_t;
using i64 = std::int64_t;
using u64 = std::uint64_t;
using isize = std::ptrdiff_t;
using usize = std::size_t;

class rep {
    struct Iter {
        usize itr;
        constexpr Iter(const usize pos) noexcept : itr(pos) {}
        constexpr void operator++() noexcept { ++itr; }
        constexpr bool operator!=(const Iter& other) const noexcept { return itr != other.itr; }
        constexpr usize operator*() const noexcept { return itr; }
    };
    const Iter first, last;

  public:
    explicit constexpr rep(const usize first, const usize last) noexcept : first(first), last(std::max(first, last)) {}
    constexpr Iter begin() const noexcept { return first; }
    constexpr Iter end() const noexcept { return last; }
};

template <class T> constexpr T totient(T x) {
    T ret = x;
    for (T i = 2; i * i <= x; ++i) {
        if (x % i == 0) {
            ret /= i;
            ret *= i - 1;
            while (x % i == 0) x /= i;
        }
    }
    if (x > 1) {
        ret /= x;
        ret *= x - 1;
    }
    return ret;
}

template <class T> constexpr T rem_euclid(T value, const T& mod) { return (value %= mod) >= 0 ? value : value + mod; }

template <u32 MOD, std::enable_if_t<((u32)1 <= MOD and MOD <= ((u32)1 << 31))>* = nullptr> class StaticModint {
    using Mint = StaticModint;

    static inline constexpr u32 PHI = totient(MOD);
    u32 v;

  public:
    static constexpr u32 mod() noexcept { return MOD; }

    template <class T, std::enable_if_t<std::is_signed_v<T> and std::is_integral_v<T>>* = nullptr>
    static constexpr T normalize(const T x) noexcept {
        return rem_euclid<std::common_type_t<T, i64>>(x, MOD);
    }
    template <class T, std::enable_if_t<std::is_unsigned_v<T> and std::is_integral_v<T>>* = nullptr>
    static constexpr T normalize(const T x) noexcept {
        return x % MOD;
    }

    constexpr StaticModint() noexcept : v(0) {}
    template <class T> constexpr StaticModint(const T x) noexcept : v(normalize(x)) {}
    template <class T> static constexpr Mint raw(const T x) noexcept {
        Mint ret;
        ret.v = x;
        return ret;
    }

    constexpr u32 get() const noexcept { return v; }
    constexpr Mint neg() const noexcept { return raw(v == 0 ? 0 : MOD - v); }
    constexpr Mint inv() const noexcept { return pow(PHI - 1); }
    constexpr Mint pow(u64 exp) const noexcept {
        Mint ret(1), mult(*this);
        for (; exp > 0; exp >>= 1) {
            if (exp & 1) ret *= mult;
            mult *= mult;
        }
        return ret;
    }

    constexpr Mint operator-() const noexcept { return neg(); }
    constexpr Mint operator~() const noexcept { return inv(); }

    constexpr Mint operator+(const Mint& rhs) const noexcept { return Mint(*this) += rhs; }
    constexpr Mint& operator+=(const Mint& rhs) noexcept {
        if ((v += rhs.v) >= MOD) v -= MOD;
        return *this;
    }

    constexpr Mint operator-(const Mint& rhs) const noexcept { return Mint(*this) -= rhs; }
    constexpr Mint& operator-=(const Mint& rhs) noexcept {
        if (v < rhs.v) v += MOD;
        v -= rhs.v;
        return *this;
    }

    constexpr Mint operator*(const Mint& rhs) const noexcept { return Mint(*this) *= rhs; }
    constexpr Mint& operator*=(const Mint& rhs) noexcept {
        v = (u64)v * rhs.v % MOD;
        return *this;
    }

    constexpr Mint operator/(const Mint& rhs) const noexcept { return Mint(*this) /= rhs; }
    constexpr Mint& operator/=(const Mint& rhs) noexcept { return *this *= rhs.inv(); }

    constexpr bool operator==(const Mint& rhs) const noexcept { return v == rhs.v; }
    constexpr bool operator!=(const Mint& rhs) const noexcept { return v != rhs.v; }
    friend std::ostream& operator<<(std::ostream& stream, const Mint& rhs) { return stream << rhs.v; }
};

using Modint1000000007 = StaticModint<1000000007>;
using Modint998244353 = StaticModint<998244353>;

__attribute__((target("avx2"))) constexpr u64 ceil_log2(const u64 x) {
    u64 e = 0;
    while (((u64)1 << e) < x) ++e;
    return e;
}

template <class F> class AutoReallocation {
    using R = typename decltype(std::declval<F>()((usize)0))::value_type;

    F func;
    mutable std::vector<R> data;

  public:
    explicit AutoReallocation(F&& f) : func(std::forward<F>(f)), data() {}

    void reserve(const usize size) const {
        if (data.size() < size) data = func(((usize)1 << ceil_log2(size)));
    }
    R operator[](const usize i) const {
        reserve(i + 1);
        return data[i];
    }
};

template <class F> decltype(auto) auto_realloc(F&& f) {
    using G = std::decay_t<F>;
    return AutoReallocation<G>(std::forward<G>(f));
}

template <class M> struct ModintUtil {
    static inline const auto fact = auto_realloc([](const usize n) {
        std::vector<M> ret(n);
        ret[0] = M(1);
        for (const usize i : rep(1, n)) {
            ret[i] = ret[i - 1] * M(i);
        }
        return ret;
    });
    static inline const auto inv = auto_realloc([](const usize n) {
        std::vector<M> ret(n);
        if (n == 1) return ret;
        ret[1] = M(1);
        for (const usize i : rep(2, n)) {
            ret[i] = -M(M::mod() / i) * ret[M::mod() % i];
        }
        return ret;
    });
    static inline const auto inv_fact = auto_realloc([](const usize n) {
        std::vector<M> ret(n);
        ret[0] = M(1);
        for (const usize i : rep(1, n)) {
            ret[i] = ret[i - 1] * inv[i];
        }
        return ret;
    });
    static M binom(const usize n, const usize k) {
        assert(k <= n);
        return fact[n] * inv_fact[n - k] * inv_fact[k];
    }
    static M factpow(const usize n, const usize k) {
        assert(k <= n);
        return fact[n] * inv_fact[n - k];
    }
    static M homo(const usize n, const usize k) {
        if (n == 0 and k == 0) return M(1);
        return binom(n + k - 1, k);
    }
};

template <class T> using Vec = std::vector<T>;

using Fp = Modint1000000007;
using Util = ModintUtil<Fp>;

Fp coeff(const usize a, const usize b) {
    if (b == 0) return a == 0;
    return Util::binom(a + b - 1, a);
}

void main_() {
    i64 A, B, X, Y;
    std::cin >> A >> B >> X >> Y;
    Fp ans;
    for (const i64 a : rep(0, A + 1)) {
        const i64 c = a - X;
        if (c < 0) continue;
        if (a + c > A) continue;
        if ((A - a - c) % 2 != ((Y % 2) + 2) % 2) continue;
        const i64 b = ((A - a - c) + Y) / 2;
        const i64 d = b - Y;
        if (b < 0 or d < 0) continue;
        assert(a + b + c + d == A);
        assert(a - c == X);
        assert(b - d == Y);
        Fp add = 1;
        add *= coeff(a, B / 4 + (B % 4 >= 0));
        add *= coeff(b, B / 4 + (B % 4 >= 1));
        add *= coeff(c, B / 4 + (B % 4 >= 2));
        add *= coeff(d, B / 4 + (B % 4 >= 3));
        ans += add;
    }
    std::cout << ans << '\n';
}

int main() {
    std::ios_base::sync_with_stdio(false);
    std::cin.tie(nullptr);
    main_();
    return 0;
}
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