#919967 (C++17) No.2503 Typical Path Counting Problem on a Grid

提出ソース
結果

問題	No.2503 Typical Path Counting Problem on a Grid
ユーザー	haruki_K
提出日時	2023-10-13 22:52:01
言語	C++17 (gcc 12.3.0 + boost 1.83.0)
結果	AC
実行時間	621 ms / 2,000 ms
コード長	20,734 bytes
コンパイル時間	2,659 ms
コンパイル使用メモリ	215,416 KB
実行使用メモリ	354,840 KB
最終ジャッジ日時	2024-09-15 18:37:26
合計ジャッジ時間	10,126 ms
ジャッジサーバーID （参考情報）	judge3 / judge2
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	579 ms 354,804 KB
testcase_01	AC	574 ms 354,688 KB
testcase_02	AC	576 ms 354,680 KB
testcase_03	AC	600 ms 354,620 KB
testcase_04	AC	621 ms 354,688 KB
testcase_05	AC	591 ms 354,816 KB
testcase_06	AC	621 ms 354,776 KB
testcase_07	AC	619 ms 354,840 KB
testcase_08	AC	593 ms 354,620 KB
testcase_09	AC	620 ms 354,688 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

raw source code
// >>> 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
using pii = pair<int, int>;
#define overload3(_1, _2, _3, f, ...) f
#define v1_rep(n) for (int _n = (n); _n--; )
#define v2_rep(i, n) if (const int _n = (n); true) for (int i = 0; i < _n; i++)
#define v3_rep(i, a, b) if (const int _b = (b); true) for (int i = (a); i < _b; i++)
#define rep(...) overload3(__VA_ARGS__, v3_rep, v2_rep, v1_rep)(__VA_ARGS__)
#define v2_repR(i, n) for (int i = (int)(n)-1; i >= 0; i--)
#define v3_repR(i, a, b) if (const int _a = (a); true) for (int i = int(b)-1; i >= _a; i--)
#define repR(...) overload3(__VA_ARGS__, v3_repR, v2_repR, v1_rep)(__VA_ARGS__)
#define rep1(i, n) if (const int _rep_n = n; true) for (int i = 1; i <= _rep_n; 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 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"
#define oj_local(x, y) (y)
#else
#define dump(...) ([]() { return false; }())
#define if_debug if (0)
#define oj_local(x, y) (x)
#endif

template <class T, class Comp> struct pque : priority_queue<T, vector<T>, Comp> {
    vector<T> &data() { return this->c; }
    void clear() { this->c.clear(); }
};
template <class T> using pque_max = pque<T, less<T>>;
template <class T> using pque_min = pque<T, greater<T>>;

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;
}
template <class... T> ostream& operator<<(ostream& os, tuple<T...> const& t) {
    bool f = true;
    apply([&](auto&&... x) { ((os << (f ? f = false, "" : " ") << x), ...); }, t);
    return os;
}
template <class... T> istream& operator>>(istream& is, tuple<T...>& t) {
    apply([&](auto&&... x) { ((is >> x), ...); }, t);
    return is;
}
template <class T, class = typename T::iterator, enable_if_t<!is_same<T, string>::value, int> = 0>
ostream& operator<<(ostream& os, T const& a) {
    bool f = true;
    for (auto const& x : a) os << (f ? "" : " ") << x, f = false;
    return os;
}
template <class T, size_t N, enable_if_t<!is_same<T, char>::value, int> = 0>
ostream& operator<<(ostream& os, const T (&a)[N]) {
    bool f = true;
    for (auto const& x : a) os << (f ? "" : " ") << x, f = false;
    return os;
}
template <class T, class = decltype(begin(declval<T&>())), class = typename enable_if<!is_same<T, string>::value>::type>
istream& operator>>(istream& is, T &a) { for (auto& x : a) is >> x; return is; }
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 def(name, ...) auto name = MakeFixPoint() | [&](auto &&name, __VA_ARGS__)

template <class F> struct FixPoint_d : private F {
    const char* const name;
    static inline int level = 0;
    constexpr FixPoint_d(F&& f, const char* name) : F(forward<F>(f)), name(name) {}
    template <class... T> constexpr auto operator()(T&&... x) const {
        if constexpr (is_same_v<void, decltype(F::operator()(*this, forward<T>(x)...))>) {
#ifdef LOCAL
            cerr << string(level, '|') << name << to_s(tuple(x...)) << '\n';
#endif
            ++level;
            F::operator()(*this, forward<T>(x)...);
            --level;
#ifdef LOCAL
            cerr << string(level, '|') << name << to_s(tuple(x...)) << " -> void" << '\n';
#endif
        } else {
#ifdef LOCAL
            cerr << string(level, '|') << name << to_s(tuple(x...)) << '\n';
#endif
            ++level;
            auto ret = F::operator()(*this, forward<T>(x)...);
            --level;
#ifdef LOCAL
            cerr << string(level, '|') << name << to_s(tuple(x...)) << " -> " << to_s(ret) << '\n';
#endif
            return ret;
        }
    }
};
struct MakeFixPoint_d {
    const char* const name;
    MakeFixPoint_d(const char* name) : name(name) {}
    template <class F> constexpr auto operator|(F&& f) const {
        return FixPoint_d<F>(forward<F>(f), name);
    }
};
#ifdef LOCAL
#define def_d(name, ...) auto name = MakeFixPoint_d(#name) | [&](auto &&name, __VA_ARGS__)
#else
#define def_d def
#endif

struct Reader {
    template <class T> T get() const{ T x; cin >> x; return x; }
    template <class T> operator T() const { return get<T>(); }
    template <class... T> void operator()(T&... args) const { ((cin >> args), ...); }
} input;

namespace impl {

template <class T, size_t d> struct mvec { using type = vector<typename mvec<T, d-1>::type>; };
template <class T> struct mvec<T, 0> { using type = T; };

template <size_t i, size_t... j>
constexpr size_t head(index_sequence<i, j...>) { return i; }

template <size_t i, size_t... j>
constexpr auto tail(index_sequence<i, j...>) { return index_sequence<j...>{}; }

template <class T, size_t... i, size_t d, class Value>
auto make_v(index_sequence<i...>, const int (&s)[d], Value const& x) {
    if constexpr (sizeof...(i) == 0) {
        return (T)x;
    } else {
        typename mvec<T, sizeof...(i)>::type ret;
        auto idx = index_sequence<i...>{};
        int n = s[head(idx)];
        if (n < 0) cerr << "[error] negative size: {" << s << "}\n", abort();
        ret.reserve(n);
        while (n-- > 0) ret.emplace_back(make_v<T>(tail(idx), s, x));
        return ret;
    }
}
} // namespace impl

template <class T, size_t d = 1> using mvec = typename impl::mvec<T, d>::type;

template <class T, size_t d, class Value> auto make_v(const int (&s)[d], Value const& x) {
    return impl::make_v<T>(make_index_sequence<d>{}, s, x);
}

template <class T, size_t d> auto make_v(const int (&s)[d]) {
    return impl::make_v<T>(make_index_sequence<d>{}, s, T{});
}

template <class T, class... Size> auto make_v(Size... s) {
    return impl::make_v<T>(make_index_sequence<sizeof...(s)>{}, (int[sizeof...(s)]){s...}, T{});
}

template <class T> void quit(T const& x) { cout << x << '\n'; exit(0); }
template <class T, class U> constexpr bool chmin(T& x, U const& y) {
    return x > y ? x = y, true : false;
}
template <class T, class U> constexpr bool chmax(T& x, U const& y) {
    return x < y ? x = y, true : false;
}
template <class It> constexpr auto sumof(It b, It e) {
    return accumulate(b, e, typename iterator_traits<It>::value_type{});
}
template <class T, class = decltype(begin(declval<T&>()))>
constexpr auto min(T const& a) { return *min_element(begin(a), end(a)); }
template <class T, class = decltype(begin(declval<T&>()))>
constexpr auto max(T const& a) { return *max_element(begin(a), end(a)); }
template <class T> constexpr T min(set<T> const& st) { assert(st.size()); return *st.begin(); }
template <class T> constexpr T max(set<T> const& st) { assert(st.size()); return *prev(st.end()); }
template <class T> constexpr T min(multiset<T> const& st) { assert(st.size()); return *st.begin(); }
template <class T> constexpr T max(multiset<T> const& st) { assert(st.size()); return *prev(st.end()); }
constexpr ll max(signed x, ll y) { return max<ll>(x, y); }
constexpr ll max(ll x, signed y) { return max<ll>(x, y); }
constexpr ll min(signed x, ll y) { return min<ll>(x, y); }
constexpr ll min(ll x, signed y) { return min<ll>(x, y); }
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(begin(v), end(v), x) - begin(v); }
template <class C, class T>
int ubd(C const& v, T const& x) { return upper_bound(begin(v), end(v), x) - begin(v); }
constexpr ll mod(ll x, ll m) { assert(m > 0); return (x %= m) < 0 ? x+m : x; }
constexpr ll div_floor(ll x, ll y) { assert(y != 0); return x/y - ((x^y) < 0 and x%y); }
constexpr ll div_ceil(ll x, ll y) { assert(y != 0); return x/y + ((x^y) > 0 and x%y); }
constexpr int dx[] = { 1, 0, -1, 0, 1, -1, -1, 1 };
constexpr int dy[] = { 0, 1, 0, -1, 1, 1, -1, -1 };
vector<int> iota(int n) {
    vector<int> idx(n);
    iota(begin(idx), end(idx), 0);
    return idx;
}
template <class Comp> vector<int> iota(int n, Comp comp) {
    vector<int> idx(n);
    iota(begin(idx), end(idx), 0);
    stable_sort(begin(idx), end(idx), comp);
    return idx;
}
constexpr int popcnt(ll x) { return __builtin_popcountll(x); }
mt19937_64 seed_{random_device{}()};
template <class Int> Int rand(Int a, Int b) { return uniform_int_distribution<Int>(a, b)(seed_); }
i64 irand(i64 a, i64 b) { return rand<i64>(a, b); } // [a, b]
u64 urand(u64 a, u64 b) { return rand<u64>(a, b); } //
template <class It> void shuffle(It l, It r) { shuffle(l, r, seed_); }
template <class V> V &operator--(V &v) { for (auto &x : v) --x; return v; }
template <class V> V &operator++(V &v) { for (auto &x : v) ++x; return v; }
bool next_product(vector<int> &v, int m) {
    repR (i, v.size()) if (++v[i] < m) return true; else v[i] = 0;
    return false;
}
bool next_product(vector<int> &v, vector<int> const& s) {
    repR (i, v.size()) if (++v[i] < s[i]) return true; else v[i] = 0;
    return false;
}
template <class Vec> int sort_unique(Vec &v) {
    sort(begin(v), end(v));
    v.erase(unique(begin(v), end(v)), end(v));
    return v.size();
}
template <class Vec, class Comp> int sort_unique(Vec &v, Comp comp) {
    sort(begin(v), end(v), comp);
    v.erase(unique(begin(v), end(v)), end(v));
    return v.size();
}
template <class It> auto prefix_sum(It l, It r) {
    vector<typename It::value_type> s = { 0 };
    while (l != r) s.emplace_back(s.back() + *l++);
    return s;
}
template <class It> auto suffix_sum(It l, It r) {
    vector<typename It::value_type> s = { 0 };
    while (l != r) s.emplace_back(*--r + s.back());
    reverse(s.begin(), s.end());
    return s;
}
template <class T> T pop(vector<T> &a) { auto x = a.back(); a.pop_back(); return x; }
template <class T> T pop_back(vector<T> &a) { auto x = a.back(); a.pop_back(); return x; }
template <class T, class V, class C> T pop(priority_queue<T, V, C> &a) { auto x = a.top(); a.pop(); return x; }
template <class T> T pop(queue<T> &a) { auto x = a.front(); a.pop(); return x; }
template <class T> T pop_front(deque<T> &a) { auto x = a.front(); a.pop_front(); return x; }
template <class T> T pop_back(deque<T> &a) { auto x = a.back(); a.pop_back(); return x; }
template <class T> T pop_front(set<T> &a) { auto x = *a.begin(); a.erase(a.begin()); return x; }
template <class T> T pop_back(set<T> &a) { auto it = prev(a.end()); auto x = *it; a.erase(it); return x; }
template <class T> T pop_front(multiset<T> &a) { auto it = a.begin(); auto x = *it; a.erase(it); return x; }
template <class T> T pop_back(multiset<T> &a) { auto it = prev(a.end()); auto x = *it; a.erase(it); return x; }
template <class A, class B>
pair<vector<A>, vector<B>> unzip(vector<pair<A, B>> const& c) {
    vector<A> a;
    vector<B> b;
    for (auto const& [x, y] : c) {
        a.push_back(x);
        b.push_back(y);
    }
    return { a, b };
}
template <class A, class B>
pair<vector<A>, vector<B>> unzip(map<A, B> const& c) {
    vector<A> a;
    vector<B> b;
    for (auto const& [x, y] : c) {
        a.push_back(x);
        b.push_back(y);
    }
    return { a, b };
}
template <class T, class... Int> auto read_v(Int... s) {
    auto x = make_v<T>(s...);
    cin >> x;
    return x;
}

template <class T> auto read_v() {
    T x;
    cin >> x;
    return x;
}

template <class... T, class... Int>
auto read(Int... s) {
    if constexpr (sizeof...(T) >= 2) {
        return read_v<tuple<T...>>(s...);
    } else {
        return read_v<T...>(s...);
    }
}

template <class T, size_t d, class... Int>
auto read(Int... s) {
    return read_v<array<T, d>>(s...);
}
// <<<
constexpr int64_t MOD = 998244353;
// >>> modint, mod table
// >>> 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 and 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; }
};
// <<<
using mint = modint<MOD>;
mint sign(int n) { return n & 1 ? -1 : +1; }
// >>> mod table
template <uint32_t mod> struct ModTable {
    static_assert(mod > 1, "");
    vector<uint32_t> fact = { 1, 1 }, finv = { 1, 1 }, inv = { 0, 1 };
    ModTable(int n = 0) {
        calc(n);
    }
    void calc(int n) {
        const int now = fact.size();
        if (n < now) return;
        assert(n < int(1e9));
        int nxt = now;
        do nxt <<= 1; while (nxt <= n);
        fact.resize(nxt);
        finv.resize(nxt);
        inv.resize(nxt);
        for (uint32_t i = now; i < nxt; i++) {
            fact[i] = uint64_t(fact[i-1]) * i % mod;
            inv[i] = mod - uint64_t(inv[mod%i]) * (mod/i) % mod;
            finv[i] = uint64_t(finv[i-1]) * inv[i] % mod;
        }
    }
};

ModTable<MOD> mod_tab;

modint<MOD> fact(int n) {
    assert(0 <= n);
    mod_tab.calc(n);
    return mod_tab.fact[n];
}
modint<MOD> finv(int n) {
    assert(0 <= n);
    mod_tab.calc(n);
    return mod_tab.finv[n];
}
modint<MOD> inv(int n) {
    assert(0 <= n);
    mod_tab.calc(n);
    return mod_tab.inv[n];
}
modint<MOD> comb(int n, int k) {
    if (k < 0) {
        return 0;
    } else if (n >= k) {
        mod_tab.calc(n);
        return (uint64_t)mod_tab.finv[k] * mod_tab.finv[n-k] % MOD * mod_tab.fact[n];
    } else if (n < 0) {
        n = -n+k-1;
        mod_tab.calc(n);
        int ans = (uint64_t)mod_tab.finv[k] * mod_tab.finv[n-k] % MOD * mod_tab.fact[n];
        if (k & 1) ans = -ans;
        return ans;
    } else {
        return 0;
    }
}
// <<<
// <<<
// >>> matrix
template <class T> struct semi_ring_one {
    template <class S>
    static decltype(S::one()) helper(signed) { return S::one(); }
    template <class S>
    static constexpr S helper(long) { return 1; }

    static T get() { return helper<T>(0); }
};

template <class T, int N, int M> struct MatrixBase {
    static_assert(N > 0 and M > 0);
    int n = N, m = M;
    array<T, N*M> a = {};
    MatrixBase() {}
    MatrixBase(int n, int m) { assert(N == n and M == m); }
};

template <class T> struct MatrixBase<T, -1, -1> {
    int n, m;
    vector<T> a;
    MatrixBase() : n(0), m(0) {}
    MatrixBase(int n, int m) : n(n), m(m), a(n*m) { assert(n > 0 and m > 0); }
};

template <class T, int N = -1, int M = -1> struct Matrix : MatrixBase<T, N, M> {
    using base = MatrixBase<T, N, M>;
    using base::base, base::n, base::m, base::a;
    Matrix(initializer_list<initializer_list<T>> init)
        : base(init.size(), init.begin()->size()) {
        int i = 0;
        for (auto const& ls : init) {
            assert((int)ls.size() == m);
            for (auto const& x : ls) {
                a[i++] = x;
            }
        }
    }
    auto operator[](int i) const {
        assert(0 <= i); assert(i < n);
        return a.begin() + i*m;
    }
    auto operator[](int i) {
        assert(0 <= i); assert(i < n);
        return a.begin() + i*m;
    }
    bool operator==(Matrix const& x) const {
        return n == x.n and m == x.m and a == x.a;
    }
    bool operator!=(Matrix const& x) const {
        return !(*this == x);
    }
    Matrix operator+() const { return *this; }
    Matrix operator+(Matrix const& x) const { return Matrix(*this) += x; }
    Matrix& operator+=(Matrix const& x) {
        assert(n == x.n and m == x.m);
        rep (i, a.size()) a[i] += x.a[i];
        return *this;
    }
    template <int L>
    Matrix<T, N, L> operator*(Matrix<T, M, L> const& x) const {
        assert(m == x.n);
        Matrix<T, N, L> ret(n, x.m);
        rep (i, n) rep (j, m) {
            auto A = ret[i];
            auto B = (*this)[i][j];
            auto C = x[j];
            rep (k, x.m) A[k] += B * C[k];
        }
        return ret;
    }
    Matrix& operator*=(Matrix const& x) {
        auto res = (*this)*x;
        swap(a, res.a);
        return *this;
    }
    Matrix operator*(T const& c) const { return Matrix(*this) *= c; }
    Matrix& operator*=(T const& c) {
        rep (i, a.size()) a[i] *= c;
        return *this;
    }
    friend Matrix operator*(T const& c, Matrix const& x) {
        Matrix ret = x;
        rep (i, ret.a.size()) ret.a[i] = c * ret.a[i];
        return ret;
    }
    static Matrix identity(int n = N) {
        static_assert(N == M);
        assert(n >= 0);
        Matrix ret(n, n);
        rep (i, n) ret[i][i] = semi_ring_one<T>::get();
        return ret;
    }
    Matrix pow(ll k) const {
        assert(n == m); assert(k >= 0);
        Matrix v = *this, r = identity(n);
        for ( ; k > 0; k >>= 1, v *= v) if (k & 1) r *= v;
        return r;
    }
    Matrix operator-() const {
        Matrix x = *this;
        rep (i, a.size()) a[i] = -a[i];
        return x;
    }
    Matrix& operator-=(Matrix const& x) {
        assert(n == x.n and m == x.m);
        rep (i, a.size()) a[i] -= x.a[i];
        return *this;
    }
    Matrix operator-(Matrix const& x) const { return Matrix(*this) -= x; }
    Matrix& operator/=(T const& c) {
        rep (i, a.size()) a[i] /= c;
        return *this;
    }
    Matrix operator/(T const& c) const {
        return Matrix(*this) /= c;
    }
    friend istream& operator>>(istream& is, Matrix& x) {
        rep (i, x.n) rep (j, x.m) is >> x[i][j];
        return is;
    }
#ifdef LOCAL
    friend string to_s(Matrix const& x) {
        string ret;
        rep (i, x.n) {
            ret += "\n(";
            rep (j, x.m) ret += " " + to_s(x[i][j]);
            ret += " )";
        }
        return ret += "\n";
    }
#endif
};
// <<<

int32_t main() {
    const int M = oj_local(1e7 + 10, 20);
    vector<mint> a(M);

    a[0] = 1;
    a[1] = 2;
    rep (i, M) if (i >= 2) {
        a[i] = 2*i*a[i-1] + (i-1)*a[i-2];
    }
    dump(a);

    vector<Matrix<mint, 2, 2>> A(M);
    A[0] = {{1, 0}, {0, 1}};
    rep (i, M-1) A[i+1] = A[i] * Matrix<mint, 2, 2>{{2*(i+1), i+1}, {1, 0}};
    dump(A);

    int t = input;
    rep (t) {
        int n = input, m = input;
        if (n > m) swap(n, m);

        Matrix<mint, 2, 2> B = {
            {2*n+1, n},
            {1, 0}
        };
        B = A[n] * B.pow(m-n);

        mint x = a[n], y = n-1 >= 0 ? a[n-1] : 0;
        cout << B[0][0]*x + B[0][1]*y << '\n';
    }
}
yukicoder

結果

テストケース

ソースコード
