結果

問題 No.1227 I hate ThREE
ユーザー haruki_Kharuki_K
提出日時 2020-09-12 01:18:30
言語 C++17
(gcc 12.3.0 + boost 1.83.0)
結果
AC  
実行時間 93 ms / 2,000 ms
コード長 7,161 bytes
コンパイル時間 2,398 ms
コンパイル使用メモリ 213,736 KB
実行使用メモリ 27,008 KB
最終ジャッジ日時 2024-06-10 14:51:29
合計ジャッジ時間 4,447 ms
ジャッジサーバーID
（参考情報） 		judge1 / judge3
このコードへのチャレンジ
（要ログイン）

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
6,812 KB
testcase_01 AC 2 ms
6,812 KB
testcase_02 AC 2 ms
6,820 KB
testcase_03 AC 27 ms
25,600 KB
testcase_04 AC 26 ms
26,240 KB
testcase_05 AC 27 ms
24,576 KB
testcase_06 AC 1 ms
6,940 KB
testcase_07 AC 1 ms
6,944 KB
testcase_08 AC 11 ms
6,940 KB
testcase_09 AC 8 ms
6,940 KB
testcase_10 AC 6 ms
6,944 KB
testcase_11 AC 80 ms
24,576 KB
testcase_12 AC 93 ms
26,752 KB
testcase_13 AC 3 ms
6,940 KB
testcase_14 AC 7 ms
6,940 KB
testcase_15 AC 11 ms
6,940 KB
testcase_16 AC 25 ms
11,904 KB
testcase_17 AC 15 ms
8,192 KB
testcase_18 AC 40 ms
15,616 KB
testcase_19 AC 30 ms
12,800 KB
testcase_20 AC 42 ms
16,896 KB
testcase_21 AC 2 ms
6,940 KB
testcase_22 AC 31 ms
13,056 KB
testcase_23 AC 62 ms
25,984 KB
testcase_24 AC 66 ms
27,008 KB
testcase_25 AC 65 ms
26,880 KB
testcase_26 AC 65 ms
24,448 KB
testcase_27 AC 68 ms
25,984 KB
testcase_28 AC 69 ms
26,624 KB
testcase_29 AC 68 ms
26,496 KB
testcase_30 AC 65 ms
25,088 KB
testcase_31 AC 66 ms
25,088 KB
testcase_32 AC 73 ms
26,368 KB
testcase_33 AC 66 ms
24,960 KB
testcase_34 AC 65 ms
25,600 KB
testcase_35 AC 66 ms
24,576 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 # 

// >>> TEMPLATES
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ld = long double;
using i32 = int32_t;
using i64 = int64_t;
using u32 = uint32_t;
using u64 = uint64_t;
#define int ll
#define double ld
#define rep(i,n) for (int i = 0; i < (int)(n); i++)
#define rep1(i,n) for (int i = 1; i <= (int)(n); i++)
#define repR(i,n) for (int i = (int)(n)-1; i >= 0; i--)
#define rep1R(i,n) for (int i = (int)(n); i >= 1; i--)
#define loop(i,a,B) for (int i = a; i B; i++)
#define loopR(i,a,B) for (int i = a; i B; i--)
#define all(x) begin(x), end(x)
#define allR(x) rbegin(x), rend(x)
#define pb push_back
#define eb emplace_back
#define mp make_pair
#define fst first
#define snd second
template <class Int> auto constexpr inf = numeric_limits<Int>::max()/2-1;
auto constexpr INF32 = inf<int32_t>;
auto constexpr INF64 = inf<int64_t>;
auto constexpr INF   = inf<int>;
#ifdef LOCAL
#include "debug.hpp"
#else
#define dump(...) (void)(0)
#define say(x) (void)(0)
#define debug if (0)
#endif
template <class T> using pque_max = priority_queue<T>;
template <class T> using pque_min = priority_queue<T, vector<T>, greater<T> >;
template <class T, class = typename T::iterator, class = typename enable_if<!is_same<T, string>::value>::type>
ostream& operator<<(ostream& os, T const& v) { bool f = true; for (auto const& x : v) os << (f ? "" : " ") << x, f = false; return os; }
template <class T, class = typename T::iterator, class = typename enable_if<!is_same<T, string>::value>::type>
istream& operator>>(istream& is, T &v) { for (auto& x : v) is >> x; return is; }
template <class T, class S> ostream& operator<<(ostream& os, pair<T,S> const& p) { return os << "(" << p.first << ", " << p.second << ")"; }
template <class T, class S> istream& operator>>(istream& is, pair<T,S>& p) { return is >> p.first >> p.second; }
struct IOSetup { IOSetup() { cin.tie(nullptr); ios::sync_with_stdio(false); cout << fixed << setprecision(15); } } iosetup;
template <class F> struct FixPoint : private F {
    constexpr FixPoint(F&& f) : F(forward<F>(f)) {}
    template <class... T> constexpr auto operator()(T&&... x) const { return F::operator()(*this, forward<T>(x)...); }
};
struct MakeFixPoint {
    template <class F> constexpr auto operator|(F&& f) const { return FixPoint<F>(forward<F>(f)); }
};
#define MFP MakeFixPoint()|
#define def(name, ...) auto name = MFP [&](auto &&name, __VA_ARGS__)
template <class T, size_t d> struct vec_impl {
    using type = vector<typename vec_impl<T,d-1>::type>;
    template <class... U> static type make_v(size_t n, U&&... x) { return type(n, vec_impl<T,d-1>::make_v(forward<U>(x)...)); }
};
template <class T> struct vec_impl<T,0> { using type = T; static type make_v(T const& x = {}) { return x; } };
template <class T, size_t d = 1> using vec = typename vec_impl<T,d>::type;
template <class T, size_t d = 1, class... Args> auto make_v(Args&&... args) { return vec_impl<T,d>::make_v(forward<Args>(args)...); }
template <class T> void quit(T const& x) { cout << x << endl; exit(0); }
template <class T, class U> constexpr bool chmin(T& x, U const& y) { if (x > y) { x = y; return true; } return false; }
template <class T, class U> constexpr bool chmax(T& x, U const& y) { if (x < y) { x = y; return true; } return false; }
template <class It> constexpr auto sumof(It b, It e) {
    using S = typename iterator_traits<It>::value_type;
    using T = conditional_t<is_signed_v<S>,i64,u64>;
    return accumulate(b,e,T{});
}
template <class T> int sz(T const& x) { return x.size(); }
template <class C, class T> int lbd(C const& v, T const& x) {
    return lower_bound(v.begin(), v.end(), x)-v.begin();
}
template <class C, class T> int ubd(C const& v, T const& x) {
    return upper_bound(v.begin(), v.end(), x)-v.begin();
}
const int dx[] = { 1,0,-1,0 };
const int dy[] = { 0,1,0,-1 };
constexpr int popcnt(ll x) { return __builtin_popcountll(x); }
template <class Int> Int rand(Int a, Int b) { // [a,b]
    static mt19937_64 mt{random_device{}()};
    return uniform_int_distribution<Int>(a,b)(mt);
}
i64 irand(i64 a, i64 b) { return rand<i64>(a,b); }
u64 urand(u64 a, u64 b) { return rand<u64>(a,b); }
// <<<
// >>> modint
template <uint32_t md>
class modint {
    static_assert(md < (1u<<31), "");
    using M = modint;
    using i64 = int64_t;
    uint32_t x;
public:
    static constexpr uint32_t mod = md;
    constexpr modint(i64 x = 0) : x((x%=md) < 0 ? x+md : x) { }
    constexpr i64 val() const { return x; }
    constexpr explicit operator i64() const { return x; }
    constexpr bool operator==(M r) const { return x == r.x; }
    constexpr bool operator!=(M r) const { return x != r.x; }
    constexpr M operator+() const { return *this; }
    constexpr M operator-() const { return M()-*this; }
    constexpr M& operator+=(M r) { x += r.x; x = (x < md ? x : x-md); return *this; }
    constexpr M& operator-=(M r) { x += md-r.x; x = (x < md ? x : x-md); return *this; }
    constexpr M& operator*=(M r) { x = (uint64_t(x)*r.x)%md; return *this; }
    constexpr M& operator/=(M r) { return *this *= r.inv(); }
    constexpr M operator+(M r) const { return M(*this) += r; }
    constexpr M operator-(M r) const { return M(*this) -= r; }
    constexpr M operator*(M r) const { return M(*this) *= r; }
    constexpr M operator/(M r) const { return M(*this) /= r; }
    friend constexpr M operator+(i64 x, M y) { return M(x)+y; }
    friend constexpr M operator-(i64 x, M y) { return M(x)-y; }
    friend constexpr M operator*(i64 x, M y) { return M(x)*y; }
    friend constexpr M operator/(i64 x, M y) { return M(x)/y; }
    constexpr M inv() const { assert(x > 0); return pow(md-2); }
    constexpr M pow(i64 n) const {
        assert(not (x == 0 && n == 0));
        if (n < 0) return inv().pow(-n);
        M v = *this, r = 1;
        for (; n > 0; n >>= 1, v *= v) if (n&1) r *= v;
        return r;
    }
#ifdef LOCAL
    friend string to_s(M r) { return to_s(r.val(), mod); }
#endif
    friend ostream& operator<<(ostream& os, M r) { return os << r.val(); }
    friend istream& operator>>(istream& is, M &r) { i64 x; is >> x; r = x; return is; }
};
// <<<
//constexpr int64_t MOD = 998244353;
constexpr int64_t MOD = 1e9+7;
using mint = modint<MOD>;

int32_t main() {
    int n,c; cin >> n >> c;
    vector<vector<int>> g(n);
    rep (_,n-1) {
        int a,b; cin >> a >> b; --a,--b;
        g[a].eb(b);
        g[b].eb(a);
    }

    const int M = 6*n+5;
    auto valid = [&](int i) { return 1 <= i && i <= c && i < M; };

    auto dp = make_v<mint,2>(n,M);
    def (dfs, int x, int p) -> void {
        for (int y : g[x]) if (y != p) dfs(y,x);

        rep (i,M) if (valid(i)) {
            dp[x][i] = 1;
            for (int y : g[x]) {
                if (y == p) continue;
                mint val = 0;
                if (valid(i-3)) val += dp[y][i-3];
                if (valid(i+3)) val += dp[y][i+3];
                dp[x][i] *= val;
            }
        }
    };
    dfs(0,-1);

    mint ans = 0;
    if (c < M) {
        rep1 (i,c) ans += dp[0][i];
    } else {
        rep1 (i,3*n) ans += dp[0][i]*2;
        ans += mint(2).pow(n-1) * (c-6*n);
    }
    cout << ans << endl;



}
0