cplib-cpp

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:heavy_check_mark: data_structure/test/link_cut_tree.noncommutative.stress.test.cpp

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// パス上の頂点更新・パス上の頂点積取得が可能な Link-Cut tree
// 各頂点に 2x2 行列を載せ,演算として行列積が入る非可換・パス上更新の例.
#define PROBLEM "https://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=ITP1_1_A" // DUMMY
#include "../link_cut_tree.hpp"
#include "../../linear_algebra_matrix/matrix.hpp"
#include "../../modint.hpp"
#include "../../random/xorshift.hpp"

#include <algorithm>
#include <cassert>
#include <cstdio>
#include <unordered_set>
#include <utility>
using namespace std;

constexpr int md = 998244353;
const int NTRY = 1000;
const int VMAX = 50;
const int QPERTRY = 1000;
const int dim = 2;
using mint = ModInt<md>;

using S = tuple<int, matrix<mint>, matrix<mint>>;
using F = pair<bool, matrix<mint>>;
S op(S l, S r) {
    int sl, sr;
    matrix<mint> ml1, ml2, mr1, mr2;
    tie(sl, ml1, ml2) = l;
    tie(sr, mr1, mr2) = r;
    return {sl + sr, mr1 * ml1, ml2 * mr2};
}
S mapping(F f, S x) {
    int sz = get<0>(x);
    if (sz) {
        auto m = f.second.pow(sz);
        return {sz, m, m};
    }
    return x;
}
S reversal(S x) { return {get<0>(x), get<2>(x), get<1>(x)}; }
F composition(F f, F g) { return f.first ? f : g; }
F id() { return {false, matrix<mint>::Identity(dim)}; }
using LCT = lazy_linkcuttree<S, F, op, reversal, mapping, composition, id>;

vector<int> connected_vertices(int N, int r, const vector<unordered_set<int>> &to) {
    vector<int> visited(N);
    vector<int> ret, tmp{r};
    while (tmp.size()) {
        int now = tmp.back();
        tmp.pop_back();
        ret.push_back(now);
        visited[now] = 1;
        for (auto nxt : to[now]) {
            if (!visited[nxt]) tmp.push_back(nxt);
        }
    }
    return ret;
}

vector<int> get_rev_path(int s, int t, int prv, const vector<unordered_set<int>> &to) {
    if (s == t) return {s};
    for (auto nxt : to[s]) {
        if (nxt == prv) continue;
        auto v = get_rev_path(nxt, t, s, to);
        if (v.size()) {
            v.push_back(s);
            return v;
        }
    }
    return {};
}

S gen_rand_a() {
    matrix<mint> ret(dim, dim);
    for (int i = 0; i < dim; i++) {
        for (int j = 0; j < dim; j++) ret[i][j] = rand_int() % md;
    }
    return {1, ret, ret};
}

int main() {
    for (int ntry = 0; ntry < NTRY; ntry++) {
        const int N = 2 + rand_int() % (VMAX - 1);

        vector<S> A(N);
        LCT tree;
        vector<LCT::Node *> nodes;

        for (int i = 0; i < N; i++) {
            A[i] = gen_rand_a();
            nodes.push_back(tree.make_node(A[i]));
        }
        vector<pair<int, int>> edges;
        vector<unordered_set<int>> to(N);

        auto try_to_add_edge = [&]() {
            int a = rand_int() % N;
            vector<int> is_cmp(N, 1);
            for (auto i : connected_vertices(N, a, to)) is_cmp[i] = 0;
            vector<int> cmp;
            for (int i = 0; i < N; i++) {
                if (is_cmp[i]) cmp.push_back(i);
            }
            if (cmp.empty()) return;
            int b = cmp[rand_int() % cmp.size()];

            edges.emplace_back(a, b);
            to[a].insert(b), to[b].insert(a);
            tree.link(nodes[a], nodes[b]);
        };

        for (int i = 0; i < N / 2; i++) try_to_add_edge();

        for (int q = 0; q < QPERTRY; q++) {
            const int tp = rand_int() % 6;
            if (tp == 0) {
                // cut() if possible
                if (edges.empty()) continue;
                int e = rand_int() % edges.size();
                int a = edges[e].first, b = edges[e].second;

                edges.erase(edges.begin() + e);
                to[a].erase(b), to[b].erase(a);
                tree.cut(nodes[a], nodes[b]);

            } else if (tp == 1) {
                // link() if possible
                try_to_add_edge();

            } else if (tp == 2) {
                // apply()
                const int u = rand_int() % N;
                auto conn = connected_vertices(N, u, to);
                int v = conn[rand_int() % conn.size()];
                const auto a = gen_rand_a();
                tree.apply(nodes[u], nodes[v], {true, get<1>(a)});

                for (auto i : get_rev_path(u, v, -1, to)) A[i] = a;

            } else if (tp == 3) {
                // prod()
                const int u = rand_int() % N;
                auto conn = connected_vertices(N, u, to);
                int v = conn[rand_int() % conn.size()];
                S ret1 = tree.prod(nodes[u], nodes[v]);

                auto ret2 = S(A[u]);
                for (auto i : get_rev_path(v, u, -1, to)) {
                    if (i != u) ret2 = op(ret2, A[i]);
                }
                assert(ret1 == ret2);

            } else if (tp == 4) {
                // set()
                const int u = rand_int() % N;
                const auto a = gen_rand_a();
                tree.set(nodes[u], a);
                A[u] = a;

            } else if (tp == 5) {
                // get()
                const int u = rand_int() % N;
                const S a = tree.get(nodes[u]);
                assert(a == A[u]);
            } else {
                exit(8);
            }
        }
    }
    puts("Hello World");
}
#line 1 "data_structure/test/link_cut_tree.noncommutative.stress.test.cpp"
// パス上の頂点更新・パス上の頂点積取得が可能な Link-Cut tree
// 各頂点に 2x2 行列を載せ,演算として行列積が入る非可換・パス上更新の例.
#define PROBLEM "https://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=ITP1_1_A" // DUMMY
#line 2 "data_structure/link_cut_tree.hpp"

// CUT begin
// Link-Cut Tree
// Reference:
// - https://www.slideshare.net/iwiwi/2-12188845
// - https://ei1333.github.io/library/structure/lct/link-cut-tree-lazy-path.cpp
template <class S, class F, S (*op)(S, S), S (*reversal)(S), S (*mapping)(F, S),
          F (*composition)(F, F), F (*id)()>
class lazy_linkcuttree {
public:
    struct Node {
        Node *l, *r, *p;
        S d, sum;
        F lz;
        bool is_reversed;
        int sz;
        Node(S val)
            : l(nullptr), r(nullptr), p(nullptr), d(val), sum(val), lz(id()), is_reversed(false),
              sz(1) {}
        bool is_root() const { return !p || (p->l != this and p->r != this); }
        template <class OStream> friend OStream &operator<<(OStream &os, const Node &n) {
            os << '[';
            if (n.l) os << *(n.l) << ',';
            os << n.d << ',';
            if (n.r) os << *(n.r);
            return os << ']';
        }
    };

protected:
    void update(Node *t) {
        if (t == nullptr) return;
        t->sz = 1;
        t->sum = t->d;
        if (t->l) {
            t->sz += t->l->sz;
            t->sum = op(t->l->sum, t->sum);
        }
        if (t->r) {
            t->sz += t->r->sz;
            t->sum = op(t->sum, t->r->sum);
        }
    }
    void all_apply(Node *a, F b) {
        a->d = mapping(b, a->d);
        a->sum = mapping(b, a->sum);
        a->lz = composition(b, a->lz);
    }
    void _toggle(Node *t) {
        auto tmp = t->l;
        t->l = t->r, t->r = tmp;
        t->sum = reversal(t->sum);
        t->is_reversed ^= true;
    }

    void push(Node *&t) {
        if (t->lz != id()) {
            if (t->l) all_apply(t->l, t->lz);
            if (t->r) all_apply(t->r, t->lz);
            t->lz = id();
        }
        if (t->is_reversed) {
            if (t->l) _toggle(t->l);
            if (t->r) _toggle(t->r);
            t->is_reversed = false;
        }
    }

    void _rot_r(Node *t) {
        Node *x = t->p, *y = x->p;
        if ((x->l = t->r)) t->r->p = x;
        t->r = x, x->p = t;
        update(x), update(t);
        if ((t->p = y)) {
            if (y->l == x) y->l = t;
            if (y->r == x) y->r = t;
            update(y);
        }
    }
    void _rot_l(Node *t) {
        Node *x = t->p, *y = x->p;
        if ((x->r = t->l)) t->l->p = x;
        t->l = x, x->p = t;
        update(x), update(t);
        if ((t->p = y)) {
            if (y->l == x) y->l = t;
            if (y->r == x) y->r = t;
            update(y);
        }
    }

    void _splay(Node *t) {
        push(t);
        while (!t->is_root()) {
            Node *q = t->p;
            if (q->is_root()) {
                push(q), push(t);
                if (q->l == t)
                    _rot_r(t);
                else
                    _rot_l(t);
            } else {
                Node *r = q->p;
                push(r), push(q), push(t);
                if (r->l == q) {
                    if (q->l == t)
                        _rot_r(q), _rot_r(t);
                    else
                        _rot_l(t), _rot_r(t);
                } else {
                    if (q->r == t)
                        _rot_l(q), _rot_l(t);
                    else
                        _rot_r(t), _rot_l(t);
                }
            }
        }
    }

public:
    [[nodiscard]] Node *make_node(S val) { return new Node(val); }

    void evert(Node *t) { expose(t), _toggle(t), push(t); }

    Node *expose(Node *t) {
        Node *rp = nullptr;
        for (Node *cur = t; cur; cur = cur->p) {
            _splay(cur);
            cur->r = rp;
            update(cur);
            rp = cur;
        }
        _splay(t);
        return rp;
    }

    void link(Node *chi, Node *par) {
        evert(chi);
        expose(par);
        chi->p = par;
        par->r = chi;
        update(par);
    }

    void cut(Node *chi) {
        expose(chi);
        Node *par = chi->l;
        chi->l = nullptr;
        update(chi);
        par->p = nullptr;
    }

    void cut(Node *u, Node *v) { evert(u), cut(v); }

    Node *lca(Node *u, Node *v) { return expose(u), expose(v); }

    void set(Node *t, S x) { expose(t), t->d = x, update(t); }

    S get(Node *t) { return expose(t), t->d; }

    void apply(Node *u, Node *v, const F &x) {
        evert(u);
        expose(v);
        all_apply(v, x);
        push(v);
    }

    S prod(Node *u, Node *v) {
        evert(u);
        expose(v);
        return v->sum;
    }

    Node *kth_parent(Node *t, int k) {
        expose(t);
        while (t) {
            push(t);
            if (t->r and t->r->sz > k) {
                t = t->r;
            } else {
                if (t->r) k -= t->r->sz;
                if (k == 0) return t;
                k--;
                t = t->l;
            }
        }
        return nullptr;
    }

    bool is_connected(Node *u, Node *v) {
        expose(u), expose(v);
        return u == v or u->p;
    }
};
/* example usage:
struct S {
    int sz, sum, lhi, rhi, inhi;
    S(int x) : sz(1), sum(x), lhi(x), rhi(x), inhi(x) {}
    S(int sz_, int sum_, int lhi_, int rhi_, int inhi_)
        : sz(sz_), sum(sum_), lhi(lhi_), rhi(rhi_), inhi(inhi_) {}
};
using F = pair<bool, int>;
S op(S l, S r) {
    return S(l.sz + r.sz, l.sum + r.sum, max(l.sum + r.lhi, l.lhi), max(l.rhi + r.sum, r.rhi),
max<int>({l.inhi, r.inhi, l.rhi + r.lhi}));
}
S reversal(S x) { return S(x.sz, x.sum, x.rhi, x.lhi, x.inhi); }
S mapping(F f, S x) {
    if (f.first) {
        auto v = f.second;
        auto sum = x.sz * v;
        return S{x.sz, sum, max(v, sum), max(v, sum), max(v, sum)};
    } else {
        return x;
    }
}
F composition(F fnew, F gold) { return fnew.first ? fnew : gold; }
F id() { return {false, 0}; }
using LCT = lazy_linkcuttree<S, F, op, reversal, mapping, composition, id>;
vector<LCT::Node*> vs;
*/
#line 2 "linear_algebra_matrix/matrix.hpp"
#include <algorithm>
#include <cassert>
#include <cmath>
#include <iterator>
#include <type_traits>
#include <utility>
#include <vector>

namespace matrix_ {
struct has_id_method_impl {
    template <class T_> static auto check(T_ *) -> decltype(T_::id(), std::true_type());
    template <class T_> static auto check(...) -> std::false_type;
};
template <class T_> struct has_id : decltype(has_id_method_impl::check<T_>(nullptr)) {};
} // namespace matrix_

template <typename T> struct matrix {
    int H, W;
    std::vector<T> elem;
    typename std::vector<T>::iterator operator[](int i) { return elem.begin() + i * W; }
    inline T &at(int i, int j) { return elem[i * W + j]; }
    inline T get(int i, int j) const { return elem[i * W + j]; }
    int height() const { return H; }
    int width() const { return W; }
    std::vector<std::vector<T>> vecvec() const {
        std::vector<std::vector<T>> ret(H);
        for (int i = 0; i < H; i++) {
            std::copy(elem.begin() + i * W, elem.begin() + (i + 1) * W, std::back_inserter(ret[i]));
        }
        return ret;
    }
    operator std::vector<std::vector<T>>() const { return vecvec(); }
    matrix() = default;
    matrix(int H, int W) : H(H), W(W), elem(H * W) {}
    matrix(const std::vector<std::vector<T>> &d) : H(d.size()), W(d.size() ? d[0].size() : 0) {
        for (auto &raw : d) std::copy(raw.begin(), raw.end(), std::back_inserter(elem));
    }

    template <typename T2, typename std::enable_if<matrix_::has_id<T2>::value>::type * = nullptr>
    static T2 _T_id() {
        return T2::id();
    }
    template <typename T2, typename std::enable_if<!matrix_::has_id<T2>::value>::type * = nullptr>
    static T2 _T_id() {
        return T2(1);
    }

    static matrix Identity(int N) {
        matrix ret(N, N);
        for (int i = 0; i < N; i++) ret.at(i, i) = _T_id<T>();
        return ret;
    }

    matrix operator-() const {
        matrix ret(H, W);
        for (int i = 0; i < H * W; i++) ret.elem[i] = -elem[i];
        return ret;
    }
    matrix operator*(const T &v) const {
        matrix ret = *this;
        for (auto &x : ret.elem) x *= v;
        return ret;
    }
    matrix operator/(const T &v) const {
        matrix ret = *this;
        const T vinv = _T_id<T>() / v;
        for (auto &x : ret.elem) x *= vinv;
        return ret;
    }
    matrix operator+(const matrix &r) const {
        matrix ret = *this;
        for (int i = 0; i < H * W; i++) ret.elem[i] += r.elem[i];
        return ret;
    }
    matrix operator-(const matrix &r) const {
        matrix ret = *this;
        for (int i = 0; i < H * W; i++) ret.elem[i] -= r.elem[i];
        return ret;
    }
    matrix operator*(const matrix &r) const {
        matrix ret(H, r.W);
        for (int i = 0; i < H; i++) {
            for (int k = 0; k < W; k++) {
                for (int j = 0; j < r.W; j++) ret.at(i, j) += this->get(i, k) * r.get(k, j);
            }
        }
        return ret;
    }
    matrix &operator*=(const T &v) { return *this = *this * v; }
    matrix &operator/=(const T &v) { return *this = *this / v; }
    matrix &operator+=(const matrix &r) { return *this = *this + r; }
    matrix &operator-=(const matrix &r) { return *this = *this - r; }
    matrix &operator*=(const matrix &r) { return *this = *this * r; }
    bool operator==(const matrix &r) const { return H == r.H and W == r.W and elem == r.elem; }
    bool operator!=(const matrix &r) const { return H != r.H or W != r.W or elem != r.elem; }
    bool operator<(const matrix &r) const { return elem < r.elem; }
    matrix pow(int64_t n) const {
        matrix ret = Identity(H);
        bool ret_is_id = true;
        if (n == 0) return ret;
        for (int i = 63 - __builtin_clzll(n); i >= 0; i--) {
            if (!ret_is_id) ret *= ret;
            if ((n >> i) & 1) ret *= (*this), ret_is_id = false;
        }
        return ret;
    }
    std::vector<T> pow_vec(int64_t n, std::vector<T> vec) const {
        matrix x = *this;
        while (n) {
            if (n & 1) vec = x * vec;
            x *= x;
            n >>= 1;
        }
        return vec;
    };
    matrix transpose() const {
        matrix ret(W, H);
        for (int i = 0; i < H; i++) {
            for (int j = 0; j < W; j++) ret.at(j, i) = this->get(i, j);
        }
        return ret;
    }
    // Gauss-Jordan elimination
    // - Require inverse for every non-zero element
    // - Complexity: O(H^2 W)
    template <typename T2, typename std::enable_if<std::is_floating_point<T2>::value>::type * = nullptr>
    static int choose_pivot(const matrix<T2> &mtr, int h, int c) noexcept {
        int piv = -1;
        for (int j = h; j < mtr.H; j++) {
            if (mtr.get(j, c) and (piv < 0 or std::abs(mtr.get(j, c)) > std::abs(mtr.get(piv, c))))
                piv = j;
        }
        return piv;
    }
    template <typename T2, typename std::enable_if<!std::is_floating_point<T2>::value>::type * = nullptr>
    static int choose_pivot(const matrix<T2> &mtr, int h, int c) noexcept {
        for (int j = h; j < mtr.H; j++) {
            if (mtr.get(j, c) != T2()) return j;
        }
        return -1;
    }
    matrix gauss_jordan() const {
        int c = 0;
        matrix mtr(*this);
        std::vector<int> ws;
        ws.reserve(W);
        for (int h = 0; h < H; h++) {
            if (c == W) break;
            int piv = choose_pivot(mtr, h, c);
            if (piv == -1) {
                c++;
                h--;
                continue;
            }
            if (h != piv) {
                for (int w = 0; w < W; w++) {
                    std::swap(mtr[piv][w], mtr[h][w]);
                    mtr.at(piv, w) *= -_T_id<T>(); // To preserve sign of determinant
                }
            }
            ws.clear();
            for (int w = c; w < W; w++) {
                if (mtr.at(h, w) != T()) ws.emplace_back(w);
            }
            const T hcinv = _T_id<T>() / mtr.at(h, c);
            for (int hh = 0; hh < H; hh++)
                if (hh != h) {
                    const T coeff = mtr.at(hh, c) * hcinv;
                    for (auto w : ws) mtr.at(hh, w) -= mtr.at(h, w) * coeff;
                    mtr.at(hh, c) = T();
                }
            c++;
        }
        return mtr;
    }
    int rank_of_gauss_jordan() const {
        for (int i = H * W - 1; i >= 0; i--) {
            if (elem[i] != 0) return i / W + 1;
        }
        return 0;
    }
    int rank() const { return gauss_jordan().rank_of_gauss_jordan(); }

    T determinant_of_upper_triangle() const {
        T ret = _T_id<T>();
        for (int i = 0; i < H; i++) ret *= get(i, i);
        return ret;
    }
    int inverse() {
        assert(H == W);
        std::vector<std::vector<T>> ret = Identity(H), tmp = *this;
        int rank = 0;
        for (int i = 0; i < H; i++) {
            int ti = i;
            while (ti < H and tmp[ti][i] == T()) ti++;
            if (ti == H) {
                continue;
            } else {
                rank++;
            }
            ret[i].swap(ret[ti]), tmp[i].swap(tmp[ti]);
            T inv = _T_id<T>() / tmp[i][i];
            for (int j = 0; j < W; j++) ret[i][j] *= inv;
            for (int j = i + 1; j < W; j++) tmp[i][j] *= inv;
            for (int h = 0; h < H; h++) {
                if (i == h) continue;
                const T c = -tmp[h][i];
                for (int j = 0; j < W; j++) ret[h][j] += ret[i][j] * c;
                for (int j = i + 1; j < W; j++) tmp[h][j] += tmp[i][j] * c;
            }
        }
        *this = ret;
        return rank;
    }
    friend std::vector<T> operator*(const matrix &m, const std::vector<T> &v) {
        assert(m.W == int(v.size()));
        std::vector<T> ret(m.H);
        for (int i = 0; i < m.H; i++) {
            for (int j = 0; j < m.W; j++) ret[i] += m.get(i, j) * v[j];
        }
        return ret;
    }
    friend std::vector<T> operator*(const std::vector<T> &v, const matrix &m) {
        assert(int(v.size()) == m.H);
        std::vector<T> ret(m.W);
        for (int i = 0; i < m.H; i++) {
            for (int j = 0; j < m.W; j++) ret[j] += v[i] * m.get(i, j);
        }
        return ret;
    }
    std::vector<T> prod(const std::vector<T> &v) const { return (*this) * v; }
    std::vector<T> prod_left(const std::vector<T> &v) const { return v * (*this); }
    template <class OStream> friend OStream &operator<<(OStream &os, const matrix &x) {
        os << "[(" << x.H << " * " << x.W << " matrix)";
        os << "\n[column sums: ";
        for (int j = 0; j < x.W; j++) {
            T s = T();
            for (int i = 0; i < x.H; i++) s += x.get(i, j);
            os << s << ",";
        }
        os << "]";
        for (int i = 0; i < x.H; i++) {
            os << "\n[";
            for (int j = 0; j < x.W; j++) os << x.get(i, j) << ",";
            os << "]";
        }
        os << "]\n";
        return os;
    }
    template <class IStream> friend IStream &operator>>(IStream &is, matrix &x) {
        for (auto &v : x.elem) is >> v;
        return is;
    }
};
#line 3 "modint.hpp"
#include <iostream>
#include <set>
#line 6 "modint.hpp"

template <int md> struct ModInt {
    using lint = long long;
    constexpr static int mod() { return md; }
    static int get_primitive_root() {
        static int primitive_root = 0;
        if (!primitive_root) {
            primitive_root = [&]() {
                std::set<int> fac;
                int v = md - 1;
                for (lint i = 2; i * i <= v; i++)
                    while (v % i == 0) fac.insert(i), v /= i;
                if (v > 1) fac.insert(v);
                for (int g = 1; g < md; g++) {
                    bool ok = true;
                    for (auto i : fac)
                        if (ModInt(g).pow((md - 1) / i) == 1) {
                            ok = false;
                            break;
                        }
                    if (ok) return g;
                }
                return -1;
            }();
        }
        return primitive_root;
    }
    int val_;
    int val() const noexcept { return val_; }
    constexpr ModInt() : val_(0) {}
    constexpr ModInt &_setval(lint v) { return val_ = (v >= md ? v - md : v), *this; }
    constexpr ModInt(lint v) { _setval(v % md + md); }
    constexpr explicit operator bool() const { return val_ != 0; }
    constexpr ModInt operator+(const ModInt &x) const {
        return ModInt()._setval((lint)val_ + x.val_);
    }
    constexpr ModInt operator-(const ModInt &x) const {
        return ModInt()._setval((lint)val_ - x.val_ + md);
    }
    constexpr ModInt operator*(const ModInt &x) const {
        return ModInt()._setval((lint)val_ * x.val_ % md);
    }
    constexpr ModInt operator/(const ModInt &x) const {
        return ModInt()._setval((lint)val_ * x.inv().val() % md);
    }
    constexpr ModInt operator-() const { return ModInt()._setval(md - val_); }
    constexpr ModInt &operator+=(const ModInt &x) { return *this = *this + x; }
    constexpr ModInt &operator-=(const ModInt &x) { return *this = *this - x; }
    constexpr ModInt &operator*=(const ModInt &x) { return *this = *this * x; }
    constexpr ModInt &operator/=(const ModInt &x) { return *this = *this / x; }
    friend constexpr ModInt operator+(lint a, const ModInt &x) { return ModInt(a) + x; }
    friend constexpr ModInt operator-(lint a, const ModInt &x) { return ModInt(a) - x; }
    friend constexpr ModInt operator*(lint a, const ModInt &x) { return ModInt(a) * x; }
    friend constexpr ModInt operator/(lint a, const ModInt &x) { return ModInt(a) / x; }
    constexpr bool operator==(const ModInt &x) const { return val_ == x.val_; }
    constexpr bool operator!=(const ModInt &x) const { return val_ != x.val_; }
    constexpr bool operator<(const ModInt &x) const {
        return val_ < x.val_;
    } // To use std::map<ModInt, T>
    friend std::istream &operator>>(std::istream &is, ModInt &x) {
        lint t;
        return is >> t, x = ModInt(t), is;
    }
    constexpr friend std::ostream &operator<<(std::ostream &os, const ModInt &x) {
        return os << x.val_;
    }

    constexpr ModInt pow(lint n) const {
        ModInt ans = 1, tmp = *this;
        while (n) {
            if (n & 1) ans *= tmp;
            tmp *= tmp, n >>= 1;
        }
        return ans;
    }

    static constexpr int cache_limit = std::min(md, 1 << 21);
    static std::vector<ModInt> facs, facinvs, invs;

    constexpr static void _precalculation(int N) {
        const int l0 = facs.size();
        if (N > md) N = md;
        if (N <= l0) return;
        facs.resize(N), facinvs.resize(N), invs.resize(N);
        for (int i = l0; i < N; i++) facs[i] = facs[i - 1] * i;
        facinvs[N - 1] = facs.back().pow(md - 2);
        for (int i = N - 2; i >= l0; i--) facinvs[i] = facinvs[i + 1] * (i + 1);
        for (int i = N - 1; i >= l0; i--) invs[i] = facinvs[i] * facs[i - 1];
    }

    constexpr ModInt inv() const {
        if (this->val_ < cache_limit) {
            if (facs.empty()) facs = {1}, facinvs = {1}, invs = {0};
            while (this->val_ >= int(facs.size())) _precalculation(facs.size() * 2);
            return invs[this->val_];
        } else {
            return this->pow(md - 2);
        }
    }
    constexpr ModInt fac() const {
        while (this->val_ >= int(facs.size())) _precalculation(facs.size() * 2);
        return facs[this->val_];
    }
    constexpr ModInt facinv() const {
        while (this->val_ >= int(facs.size())) _precalculation(facs.size() * 2);
        return facinvs[this->val_];
    }
    constexpr ModInt doublefac() const {
        lint k = (this->val_ + 1) / 2;
        return (this->val_ & 1) ? ModInt(k * 2).fac() / (ModInt(2).pow(k) * ModInt(k).fac())
                                : ModInt(k).fac() * ModInt(2).pow(k);
    }

    constexpr ModInt nCr(int r) const {
        if (r < 0 or this->val_ < r) return ModInt(0);
        return this->fac() * (*this - r).facinv() * ModInt(r).facinv();
    }

    constexpr ModInt nPr(int r) const {
        if (r < 0 or this->val_ < r) return ModInt(0);
        return this->fac() * (*this - r).facinv();
    }

    static ModInt binom(int n, int r) {
        static long long bruteforce_times = 0;

        if (r < 0 or n < r) return ModInt(0);
        if (n <= bruteforce_times or n < (int)facs.size()) return ModInt(n).nCr(r);

        r = std::min(r, n - r);

        ModInt ret = ModInt(r).facinv();
        for (int i = 0; i < r; ++i) ret *= n - i;
        bruteforce_times += r;

        return ret;
    }

    // Multinomial coefficient, (k_1 + k_2 + ... + k_m)! / (k_1! k_2! ... k_m!)
    // Complexity: O(sum(ks))
    template <class Vec> static ModInt multinomial(const Vec &ks) {
        ModInt ret{1};
        int sum = 0;
        for (int k : ks) {
            assert(k >= 0);
            ret *= ModInt(k).facinv(), sum += k;
        }
        return ret * ModInt(sum).fac();
    }

    // Catalan number, C_n = binom(2n, n) / (n + 1)
    // C_0 = 1, C_1 = 1, C_2 = 2, C_3 = 5, C_4 = 14, ...
    // https://oeis.org/A000108
    // Complexity: O(n)
    static ModInt catalan(int n) {
        if (n < 0) return ModInt(0);
        return ModInt(n * 2).fac() * ModInt(n + 1).facinv() * ModInt(n).facinv();
    }

    ModInt sqrt() const {
        if (val_ == 0) return 0;
        if (md == 2) return val_;
        if (pow((md - 1) / 2) != 1) return 0;
        ModInt b = 1;
        while (b.pow((md - 1) / 2) == 1) b += 1;
        int e = 0, m = md - 1;
        while (m % 2 == 0) m >>= 1, e++;
        ModInt x = pow((m - 1) / 2), y = (*this) * x * x;
        x *= (*this);
        ModInt z = b.pow(m);
        while (y != 1) {
            int j = 0;
            ModInt t = y;
            while (t != 1) j++, t *= t;
            z = z.pow(1LL << (e - j - 1));
            x *= z, z *= z, y *= z;
            e = j;
        }
        return ModInt(std::min(x.val_, md - x.val_));
    }
};
template <int md> std::vector<ModInt<md>> ModInt<md>::facs = {1};
template <int md> std::vector<ModInt<md>> ModInt<md>::facinvs = {1};
template <int md> std::vector<ModInt<md>> ModInt<md>::invs = {0};

using ModInt998244353 = ModInt<998244353>;
// using mint = ModInt<998244353>;
// using mint = ModInt<1000000007>;
#line 2 "random/xorshift.hpp"
#include <cstdint>

// CUT begin
uint32_t rand_int() // XorShift random integer generator
{
    static uint32_t x = 123456789, y = 362436069, z = 521288629, w = 88675123;
    uint32_t t = x ^ (x << 11);
    x = y;
    y = z;
    z = w;
    return w = (w ^ (w >> 19)) ^ (t ^ (t >> 8));
}
double rand_double() { return (double)rand_int() / UINT32_MAX; }
#line 8 "data_structure/test/link_cut_tree.noncommutative.stress.test.cpp"

#line 11 "data_structure/test/link_cut_tree.noncommutative.stress.test.cpp"
#include <cstdio>
#include <unordered_set>
#line 14 "data_structure/test/link_cut_tree.noncommutative.stress.test.cpp"
using namespace std;

constexpr int md = 998244353;
const int NTRY = 1000;
const int VMAX = 50;
const int QPERTRY = 1000;
const int dim = 2;
using mint = ModInt<md>;

using S = tuple<int, matrix<mint>, matrix<mint>>;
using F = pair<bool, matrix<mint>>;
S op(S l, S r) {
    int sl, sr;
    matrix<mint> ml1, ml2, mr1, mr2;
    tie(sl, ml1, ml2) = l;
    tie(sr, mr1, mr2) = r;
    return {sl + sr, mr1 * ml1, ml2 * mr2};
}
S mapping(F f, S x) {
    int sz = get<0>(x);
    if (sz) {
        auto m = f.second.pow(sz);
        return {sz, m, m};
    }
    return x;
}
S reversal(S x) { return {get<0>(x), get<2>(x), get<1>(x)}; }
F composition(F f, F g) { return f.first ? f : g; }
F id() { return {false, matrix<mint>::Identity(dim)}; }
using LCT = lazy_linkcuttree<S, F, op, reversal, mapping, composition, id>;

vector<int> connected_vertices(int N, int r, const vector<unordered_set<int>> &to) {
    vector<int> visited(N);
    vector<int> ret, tmp{r};
    while (tmp.size()) {
        int now = tmp.back();
        tmp.pop_back();
        ret.push_back(now);
        visited[now] = 1;
        for (auto nxt : to[now]) {
            if (!visited[nxt]) tmp.push_back(nxt);
        }
    }
    return ret;
}

vector<int> get_rev_path(int s, int t, int prv, const vector<unordered_set<int>> &to) {
    if (s == t) return {s};
    for (auto nxt : to[s]) {
        if (nxt == prv) continue;
        auto v = get_rev_path(nxt, t, s, to);
        if (v.size()) {
            v.push_back(s);
            return v;
        }
    }
    return {};
}

S gen_rand_a() {
    matrix<mint> ret(dim, dim);
    for (int i = 0; i < dim; i++) {
        for (int j = 0; j < dim; j++) ret[i][j] = rand_int() % md;
    }
    return {1, ret, ret};
}

int main() {
    for (int ntry = 0; ntry < NTRY; ntry++) {
        const int N = 2 + rand_int() % (VMAX - 1);

        vector<S> A(N);
        LCT tree;
        vector<LCT::Node *> nodes;

        for (int i = 0; i < N; i++) {
            A[i] = gen_rand_a();
            nodes.push_back(tree.make_node(A[i]));
        }
        vector<pair<int, int>> edges;
        vector<unordered_set<int>> to(N);

        auto try_to_add_edge = [&]() {
            int a = rand_int() % N;
            vector<int> is_cmp(N, 1);
            for (auto i : connected_vertices(N, a, to)) is_cmp[i] = 0;
            vector<int> cmp;
            for (int i = 0; i < N; i++) {
                if (is_cmp[i]) cmp.push_back(i);
            }
            if (cmp.empty()) return;
            int b = cmp[rand_int() % cmp.size()];

            edges.emplace_back(a, b);
            to[a].insert(b), to[b].insert(a);
            tree.link(nodes[a], nodes[b]);
        };

        for (int i = 0; i < N / 2; i++) try_to_add_edge();

        for (int q = 0; q < QPERTRY; q++) {
            const int tp = rand_int() % 6;
            if (tp == 0) {
                // cut() if possible
                if (edges.empty()) continue;
                int e = rand_int() % edges.size();
                int a = edges[e].first, b = edges[e].second;

                edges.erase(edges.begin() + e);
                to[a].erase(b), to[b].erase(a);
                tree.cut(nodes[a], nodes[b]);

            } else if (tp == 1) {
                // link() if possible
                try_to_add_edge();

            } else if (tp == 2) {
                // apply()
                const int u = rand_int() % N;
                auto conn = connected_vertices(N, u, to);
                int v = conn[rand_int() % conn.size()];
                const auto a = gen_rand_a();
                tree.apply(nodes[u], nodes[v], {true, get<1>(a)});

                for (auto i : get_rev_path(u, v, -1, to)) A[i] = a;

            } else if (tp == 3) {
                // prod()
                const int u = rand_int() % N;
                auto conn = connected_vertices(N, u, to);
                int v = conn[rand_int() % conn.size()];
                S ret1 = tree.prod(nodes[u], nodes[v]);

                auto ret2 = S(A[u]);
                for (auto i : get_rev_path(v, u, -1, to)) {
                    if (i != u) ret2 = op(ret2, A[i]);
                }
                assert(ret1 == ret2);

            } else if (tp == 4) {
                // set()
                const int u = rand_int() % N;
                const auto a = gen_rand_a();
                tree.set(nodes[u], a);
                A[u] = a;

            } else if (tp == 5) {
                // get()
                const int u = rand_int() % N;
                const S a = tree.get(nodes[u]);
                assert(a == A[u]);
            } else {
                exit(8);
            }
        }
    }
    puts("Hello World");
}
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