結果

問題 No.3194 Do Optimize Your Solution
ユーザー noya2
提出日時 2025-06-23 02:55:55
言語 C++23
(gcc 13.3.0 + boost 1.87.0)
結果
WA  
実行時間 -
コード長 29,632 bytes
コンパイル時間 4,545 ms
コンパイル使用メモリ 317,068 KB
実行使用メモリ 58,448 KB
最終ジャッジ日時 2025-06-27 20:50:34
合計ジャッジ時間 13,459 ms
ジャッジサーバーID
(参考情報)
judge1 / judge2
このコードへのチャレンジ
(要ログイン)
ファイルパターン 結果
sample AC * 2
other WA * 1 TLE * 2 -- * 14
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 #

#line 2 "/Users/noya2/Desktop/Noya2_library/template/template.hpp"
using namespace std;

#include<bits/stdc++.h>
#line 1 "/Users/noya2/Desktop/Noya2_library/template/inout_old.hpp"
namespace noya2 {

template <typename T, typename U>
ostream &operator<<(ostream &os, const pair<T, U> &p){
    os << p.first << " " << p.second;
    return os;
}
template <typename T, typename U>
istream &operator>>(istream &is, pair<T, U> &p){
    is >> p.first >> p.second;
    return is;
}

template <typename T>
ostream &operator<<(ostream &os, const vector<T> &v){
    int s = (int)v.size();
    for (int i = 0; i < s; i++) os << (i ? " " : "") << v[i];
    return os;
}
template <typename T>
istream &operator>>(istream &is, vector<T> &v){
    for (auto &x : v) is >> x;
    return is;
}

void in() {}
template <typename T, class... U>
void in(T &t, U &...u){
    cin >> t;
    in(u...);
}

void out() { cout << "\n"; }
template <typename T, class... U, char sep = ' '>
void out(const T &t, const U &...u){
    cout << t;
    if (sizeof...(u)) cout << sep;
    out(u...);
}

template<typename T>
void out(const vector<vector<T>> &vv){
    int s = (int)vv.size();
    for (int i = 0; i < s; i++) out(vv[i]);
}

struct IoSetup {
    IoSetup(){
        cin.tie(nullptr);
        ios::sync_with_stdio(false);
        cout << fixed << setprecision(15);
        cerr << fixed << setprecision(7);
    }
} iosetup_noya2;

} // namespace noya2
#line 1 "/Users/noya2/Desktop/Noya2_library/template/const.hpp"
namespace noya2{

const int iinf = 1'000'000'007;
const long long linf = 2'000'000'000'000'000'000LL;
const long long mod998 =  998244353;
const long long mod107 = 1000000007;
const long double pi = 3.14159265358979323;
const vector<int> dx = {0,1,0,-1,1,1,-1,-1};
const vector<int> dy = {1,0,-1,0,1,-1,-1,1};
const string ALP = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
const string alp = "abcdefghijklmnopqrstuvwxyz";
const string NUM = "0123456789";

void yes(){ cout << "Yes\n"; }
void no(){ cout << "No\n"; }
void YES(){ cout << "YES\n"; }
void NO(){ cout << "NO\n"; }
void yn(bool t){ t ? yes() : no(); }
void YN(bool t){ t ? YES() : NO(); }

} // namespace noya2
#line 2 "/Users/noya2/Desktop/Noya2_library/template/utils.hpp"

#line 6 "/Users/noya2/Desktop/Noya2_library/template/utils.hpp"

namespace noya2{

unsigned long long inner_binary_gcd(unsigned long long a, unsigned long long b){
    if (a == 0 || b == 0) return a + b;
    int n = __builtin_ctzll(a); a >>= n;
    int m = __builtin_ctzll(b); b >>= m;
    while (a != b) {
        int mm = __builtin_ctzll(a - b);
        bool f = a > b;
        unsigned long long c = f ? a : b;
        b = f ? b : a;
        a = (c - b) >> mm;
    }
    return a << std::min(n, m);
}

template<typename T> T gcd_fast(T a, T b){ return static_cast<T>(inner_binary_gcd(std::abs(a),std::abs(b))); }

long long sqrt_fast(long long n) {
    if (n <= 0) return 0;
    long long x = sqrt(n);
    while ((x + 1) * (x + 1) <= n) x++;
    while (x * x > n) x--;
    return x;
}

template<typename T> T floor_div(const T n, const T d) {
    assert(d != 0);
    return n / d - static_cast<T>((n ^ d) < 0 && n % d != 0);
}

template<typename T> T ceil_div(const T n, const T d) {
    assert(d != 0);
    return n / d + static_cast<T>((n ^ d) >= 0 && n % d != 0);
}

template<typename T> void uniq(std::vector<T> &v){
    std::sort(v.begin(),v.end());
    v.erase(unique(v.begin(),v.end()),v.end());
}

template <typename T, typename U> inline bool chmin(T &x, U y) { return (y < x) ? (x = y, true) : false; }

template <typename T, typename U> inline bool chmax(T &x, U y) { return (x < y) ? (x = y, true) : false; }

template<typename T> inline bool range(T l, T x, T r){ return l <= x && x < r; }

} // namespace noya2
#line 8 "/Users/noya2/Desktop/Noya2_library/template/template.hpp"

#define rep(i,n) for (int i = 0; i < (int)(n); i++)
#define repp(i,m,n) for (int i = (m); i < (int)(n); i++)
#define reb(i,n) for (int i = (int)(n-1); i >= 0; i--)
#define all(v) (v).begin(),(v).end()

using ll = long long;
using ld = long double;
using uint = unsigned int;
using ull = unsigned long long;
using pii = pair<int,int>;
using pll = pair<ll,ll>;
using pil = pair<int,ll>;
using pli = pair<ll,int>;

namespace noya2{

/* ~ (. _________ . /) */

}

using namespace noya2;


#line 2 "c26.cpp"

#line 2 "/Users/noya2/Desktop/Noya2_library/tree/centroid_decomposition.hpp"

#line 4 "/Users/noya2/Desktop/Noya2_library/tree/centroid_decomposition.hpp"

namespace noya2 {

std::vector<int> centroid_decomposition(const auto &g){
    int n = g.size();
    if (n == 0){
        return {};
    }
    std::vector<int> sub(n), order;
    order.reserve(n);
    auto subtree = [&](auto sfs, int v, int f) -> void {
        sub[v] = 1;
        for (int u : g[v]){
            if (u == f) continue;
            sfs(sfs, u, v);
            sub[v] += sub[u];
        }
    };
    subtree(subtree,0,-1);
    auto fixed_root = [&](auto self, int root, int par, int cur_size) -> void {
        auto dfs = [&](auto sfs, int v, int f, int sz) -> int {
            int heavy = 0, child = -1;
            for (int u : g[v]){
                if (u == f) continue;
                if (heavy < sub[u]){
                    heavy = sub[u];
                    child = u;
                }
            }
            if (heavy > sz/2){
                int ret = sfs(sfs, child, v, sz);
                sub[v] -= ret;
                return ret;
            }
            else {
                order.emplace_back(v);
                for (int u : g[v]){
                    if (u == f) continue;
                    self(self, u, v, sub[u]);
                }
                int ret = sub[v];
                sub[v] = 0;
                return ret;
            }
        };
        while (cur_size > 0){
            cur_size -= dfs(dfs, root, par, cur_size);
        }
    };
    fixed_root(fixed_root, 0, -1, n);
    return order;
}

std::vector<int> centroid_decomposition_tree(const auto &g){
    int n = g.size();
    if (n == 0){
        return {};
    }
    std::vector<int> sub(n), par_tree(n);
    auto subtree = [&](auto sfs, int v, int f) -> void {
        sub[v] = 1;
        for (int u : g[v]){
            if (u == f) continue;
            sfs(sfs, u, v);
            sub[v] += sub[u];
        }
    };
    subtree(subtree,0,-1);
    auto fixed_root = [&](auto self, int root, int par, int cur_size, int cpre) -> void {
        auto dfs = [&](auto sfs, int v, int f, int sz) -> int {
            int heavy = 0, child = -1;
            for (int u : g[v]){
                if (u == f) continue;
                if (heavy < sub[u]){
                    heavy = sub[u];
                    child = u;
                }
            }
            if (heavy > sz/2){
                int ret = sfs(sfs, child, v, sz);
                sub[v] -= ret;
                return ret;
            }
            else {
                par_tree[v] = cpre;
                for (int u : g[v]){
                    if (u == f) continue;
                    self(self, u, v, sub[u], v);
                }
                int ret = sub[v];
                cpre = v;
                sub[v] = 0;
                return ret;
            }
        };
        while (cur_size > 0){
            cur_size -= dfs(dfs, root, par, cur_size);
        }
    };
    fixed_root(fixed_root, 0, -1, n, -1);
    return par_tree;
}

} // namespace noya2
#line 2 "/Users/noya2/Desktop/Noya2_library/tree/simple_tree.hpp"

#line 2 "/Users/noya2/Desktop/Noya2_library/data_structure/csr.hpp"

#line 4 "/Users/noya2/Desktop/Noya2_library/data_structure/csr.hpp"
#include<ranges>
#line 7 "/Users/noya2/Desktop/Noya2_library/data_structure/csr.hpp"

namespace noya2::internal {

template<class E>
struct csr {
    csr () {}
    csr (int _n) : n(_n) {}
    csr (int _n, int m) : n(_n){
        start.reserve(m);
        elist.reserve(m);
    }
    // ACL style constructor (do not have to call build)
    csr (int _n, const std::vector<std::pair<int,E>> &idx_elem) : n(_n), start(_n + 2), elist(idx_elem.size()) {
        for (auto &[i, e] : idx_elem){
            start[i + 2]++;
        }
        for (int i = 1; i < n; i++){
            start[i + 2] += start[i + 1];
        }
        for (auto &[i, e] : idx_elem){
            elist[start[i + 1]++] = e;
        }
        prepared = true;
    }
    int add(int idx, E elem){
        int eid = start.size();
        start.emplace_back(idx);
        elist.emplace_back(elem);
        return eid;
    }
    void build(){
        if (prepared) return ;
        int m = start.size();
        std::vector<E> nelist(m);
        std::vector<int> nstart(n + 2, 0);
        for (int i = 0; i < m; i++){
            nstart[start[i] + 2]++;
        }
        for (int i = 1; i < n; i++){
            nstart[i + 2] += nstart[i + 1];
        }
        for (int i = 0; i < m; i++){
            nelist[nstart[start[i] + 1]++] = elist[i];
        }
        swap(elist,nelist);
        swap(start,nstart);
        prepared = true;
    }
    const auto operator[](int idx) const {
        return std::ranges::subrange(elist.begin()+start[idx],elist.begin()+start[idx+1]);
    }
    auto operator[](int idx){
        return std::ranges::subrange(elist.begin()+start[idx],elist.begin()+start[idx+1]);
    }
    const auto operator()(int idx, int l, int r) const {
        return std::ranges::subrange(elist.begin()+start[idx]+l,elist.begin()+start[idx]+r);
    }
    auto operator()(int idx, int l, int r){
        return std::ranges::subrange(elist.begin()+start[idx]+l,elist.begin()+start[idx]+r);
    }
    size_t size() const {
        return n;
    }
    int n;
    std::vector<int> start;
    std::vector<E> elist;
    bool prepared = false;
};

} // namespace noya2::internal
#line 5 "/Users/noya2/Desktop/Noya2_library/tree/simple_tree.hpp"

namespace noya2 {

struct simple_tree {
    internal::csr<int> g;
    simple_tree () {}
    simple_tree (int _n) : g(_n, (_n - 1)*2) {
        if (_n == 1){
            g.build();
        }
    }
    void add_edge(int u, int v){
        g.add(u, v);
        int id = g.add(v, u);
        if (id + 1 == (g.n - 1)*2) g.build();
    }
    void input(int indexed = 1){
        for (int i = 0; i < g.n - 1; i++){
            int u, v; cin >> u >> v;
            u -= indexed, v -= indexed;
            add_edge(u, v);
        }
    }
    void input_parents(int indexed = 1){
        for (int i = 0; i < g.n - 1; i++){
            int v; cin >> v;
            v -= indexed;
            add_edge(i + 1, v);
        }
    }
    const auto operator[](int v) const {
        return g[v];
    }
    auto operator[](int v){
        return g[v];
    }
    size_t size() const {
        return g.size();
    }
};

} // namespace noya2
#line 2 "/Users/noya2/Desktop/Noya2_library/tree/heavy_light_decomposition.hpp"

#line 9 "/Users/noya2/Desktop/Noya2_library/tree/heavy_light_decomposition.hpp"

#line 11 "/Users/noya2/Desktop/Noya2_library/tree/heavy_light_decomposition.hpp"

namespace noya2 {

struct hld_tree {
    int n, root;
    bool build_ok = false;
    std::vector<int> down, nxt, sub, tour;
	noya2::internal::csr<int> childs;

    // default constructor (nop)
    hld_tree () {}

    // tree with _n node
    // after construct, call input_edges / input_parents / add_edge _n - 1 times
    hld_tree (int _n, int _root = 0) : n(_n), root(_root), down(n), nxt(n), sub(n, 1), tour(n) {
        if (n == 1){
            nxt[0] = -1;
            down[0] = -1;
            build_from_parents();
        }
    }

    // par[i] < i, par[0] == -1
    hld_tree (const std::vector<int> &par) : n(par.size()), root(0), down(n, -1), nxt(par), sub(n, 1), tour(n){
        build_from_parents();
    }

    // par[i] < i, par[0] == -1
    hld_tree (std::vector<int> &&par) : n(par.size()), root(0), down(n, -1), sub(n, 1), tour(n) {
        nxt.swap(par);
        build_from_parents();
    }

    // distinct unweighted undirected n - 1 edges of tree 
    hld_tree (const std::vector<std::pair<int, int>> &es, int _root = 0) : n(es.size() + 1), root(_root), down(n), nxt(n), sub(n, 1), tour(n) {
        for (auto &[u, v] : es){
            down[u]++;
            down[v]++;
            nxt[u] ^= v;
            nxt[v] ^= u;
        }
        build_from_edges();
    }

    // input parents from cin
    template<int indexed = 1>
    void input_parents(){
        using std::cin;
        nxt[0] = -1;
        down[0] = -1;
        for (int u = 1; u < n; u++){
            cin >> nxt[u];
            nxt[u] -= indexed;
            down[u] = -1;
        }
        build_from_parents();
    }

    // input n - 1 edges from cin
    template<int indexed = 1>
    void input_edges(){
        using std::cin;
        for (int i = 1; i < n; i++){
            int u, v; cin >> u >> v;
            u -= indexed;
            v -= indexed;
            down[u]++;
            down[v]++;
            nxt[u] ^= v;
            nxt[v] ^= u;
        }
        build_from_edges();
    }

    void add_edge(int u, int v){
        down[u]++;
        down[v]++;
        nxt[u] ^= v;
        nxt[v] ^= u;
        // use tour[0] as counter
        if (++tour[0] == n - 1){
            build_from_edges();
        }
    }

    size_t size() const {
        return n;
    }

    // top vertex of heavy path which contains v
    int leader(int v) const {
        return nxt[v] < 0 ? v : nxt[v];
    }

    // level ancestor
    // ret is ancestor of v, dist(ret, v) == d
    // if d > depth(v), return -1
    int la(int v, int d) const {
        while (v != -1){
            int u = leader(v);
            if (down[v] - d >= down[u]){
                v = tour[down[v] - d];
                break;
            }
            d -= down[v] - down[u] + 1;
            v = (u == root ? -1 : ~nxt[u]);
        }
        return v;
    }

    // lowest common ancestor of u and v
    int lca(int u, int v) const {
        int du = down[u], dv = down[v];
        if (du > dv){
            std::swap(du, dv);
            std::swap(u, v);
        }
        if (dv < du + sub[u]){
            return u;
        }
        while (du < dv){
            v = ~nxt[leader(v)];
            dv = down[v];
        }
        return v;
    }

    // distance from u to v
    int dist(int u, int v) const {
        int _dist = 0;
        while (leader(u) != leader(v)){
            if (down[u] > down[v]) std::swap(u, v);
            _dist += down[v] - down[leader(v)] + 1;
            v = ~nxt[leader(v)];
        }
        _dist += std::abs(down[u] - down[v]);
        return _dist;
    }

    // d times move from to its neighbor (direction of to)
    // if d > dist(from, to), return -1
    int jump(int from, int to, int d) const {
        int _from = from, _to = to;
        int dist_from_lca = 0, dist_to_lca = 0;
        while (leader(_from) != leader(_to)){
            if (down[_from] > down[_to]){
                dist_from_lca += down[_from] - down[leader(_from)] + 1;
                _from = ~nxt[leader(_from)];
            }
            else {
                dist_to_lca += down[_to] - down[leader(_to)] + 1;
                _to = ~nxt[leader(_to)];
            }
        }
        if (down[_from] > down[_to]){
            dist_from_lca += down[_from] - down[_to];
        }
        else {
            dist_to_lca += down[_to] - down[_from];
        }
        if (d <= dist_from_lca){
            return la(from, d);
        }
        d -= dist_from_lca;
        if (d <= dist_to_lca){
            return la(to, dist_to_lca - d);
        }
        return -1;
    }

    // parent of v (if v is root, return -1)
    int parent(int v) const {
        if (v == root) return -1;
        return (nxt[v] < 0 ? ~nxt[v] : tour[down[v] - 1]);
    }

    // visiting time in euler tour
    // usage : seg.set(index(v), X[v])
    int index(int vertex) const {
        return down[vertex];
    }
    // usage : seg.set(index_edge(e.u, e.v), e.val)
    int index(int vertex1, int vertex2) const {
        return std::max(down[vertex1], down[vertex2]);
    }

    // subtree size of v
    int subtree_size(int v) const {
        return sub[v];
    }

    // prod in subtree v : seg.prod(subtree_l(v), subtree_r(v))
    int subtree_l(int v) const {
        return down[v];
    }
    int subtree_r(int v) const {
        return down[v] + sub[v];
    }

    // v is in subtree r
    bool is_in_subtree(int r, int v) const {
        return subtree_l(r) <= subtree_l(v) && subtree_r(v) <= subtree_r(r);
    }
    
    // distance table from s
    std::vector<int> dist_table(int s) const {
        std::vector<int> table(n, -1);
        table[s] = 0;
        while (s != root){
            table[parent(s)] = table[s] + 1;
            s = parent(s);
        }
        for (int v : tour){
            if (table[v] == -1){
                table[v] = table[parent(v)] + 1;
            }
        }
        return table;
    }

    // dist, v1, v2
    std::tuple<int, int, int> diameter() const {
        std::vector<int> dep = dist_table(root);
        int v1 = std::ranges::max_element(dep) - dep.begin();
        std::vector<int> fromv1 = dist_table(v1);
        int v2 = std::ranges::max_element(fromv1) - fromv1.begin();
        return {fromv1[v2], v1, v2};
    }

    // vertex array {from, ..., to}
    std::vector<int> path(int from, int to) const {
        int d = dist(from, to);
        std::vector<int> _path(d + 1);
        int front = 0, back = d;
        while (from != to){
            if (down[from] > down[to]){
                _path[front++] = from;
                from = parent(from);
            }
            else {
                _path[back--] = to;
                to = parent(to);
            }
        }
        _path[front] = from;
        return _path;
    }

    // path decomposition and query (vertex weighted)
    // if l < r, decsending order tour[l, r)
    // if l > r, acsending order tour(l, r]
    template<bool vertex = true>
    void path_query(int u, int v, auto f) const {
        while (leader(u) != leader(v)){
            if (down[u] < down[v]){
                f(down[leader(v)], down[v] + 1);
                v = ~nxt[leader(v)];
            }
            else {
                f(down[u] + 1, down[leader(u)]);
                u = ~nxt[leader(u)];
            }
        }
        if constexpr (vertex){
            if (down[u] < down[v]){
                f(down[u], down[v] + 1);
            }
            else {
                f(down[u] + 1, down[v]);
            }
        }
        else {
            if (down[u] != down[v]){
                f(down[u] + 1, down[v] + 1);
            }
        }
    }

    // {parent, mapping} : cptree i is correspond to tree mapping[i]. parent[i] is parent of i in cptree.
    // parent[i] < i, parent[0] == -1
	std::pair<std::vector<int>, std::vector<int>> compressed_tree(std::vector<int> vs) const {
        if (vs.empty()){
            return {{},{}};
        }
        auto comp = [&](int l, int r){
            return down[l] < down[r];
        };
		std::ranges::sort(vs, comp);
		int sz = vs.size(); vs.reserve(2*sz);
        for (int i = 0; i < sz-1; i++){
            vs.emplace_back(lca(vs[i], vs[i+1]));
        }
        std::sort(vs.begin() + sz, vs.end(), comp);
        std::ranges::inplace_merge(vs, vs.begin() + sz, comp);
        auto del = std::ranges::unique(vs);
        vs.erase(del.begin(), del.end());
        sz = vs.size();
        std::stack<int> st;
        std::vector<int> par(sz);
        par[0] = -1;
        st.push(0);
        for (int i = 1; i < sz; i++){
            while (!is_in_subtree(vs[st.top()], vs[i])) st.pop();
            par[i] = st.top();
            st.push(i);
        }
        return {par, vs};
	}

//*  CSR

	// build csr for using operator()
    // g(v).front() : heady child of v
	void build_csr(){
		childs = noya2::internal::csr<int>(n, n - 1);
        for (int v = 0; v < n; v++){
            if (v == root) continue;
            if (leader(v) != v){
                childs.add(parent(v),v);
            }
        }
		for (int v = 0; v < n; v++){
			if (v == root) continue;
            if (leader(v) == v){
                childs.add(parent(v),v);
            }
		}
		childs.build();
	}
	const auto operator()(int v) const {
		return childs[v];
	}
	auto operator()(int v){
		return childs[v];
	}
//*/

    // hld_tree g;
    // euler tour order : `for (int v : g)`
    // with range_adaptor : `for (int v : g | std::views::reverse)`
    // bottom-up DP : `for (int v : g | std::views::drop(1) | std::views::reverse){ update dp[g.parent(v)] by dp[v] }`
    auto begin() const {
        return tour.begin();
    }
    auto end() const {
        return tour.end();
    }

  private:
    // nxt[v] : parent of v, nxt[0] == -1
    void build_from_parents(){
        for (int u = n - 1; u >= 1; u--){
            int v = nxt[u];
            sub[v] += sub[u];
            down[v] = std::max(down[v], sub[u]);
        }
        for (int u = n - 1; u >= 1; u--){
            int v = nxt[u];
            if (down[v] == sub[u]){
                sub[u] = ~sub[u];
                down[v] = ~down[v];
            }
        }

        sub[0] = ~down[0] + 1;
        down[0] = 0;
        for (int u = 1; u < n; u++){
            int v = nxt[u];
            int nsub = ~down[u] + 1;
            if (sub[u] < 0){
                down[u] = down[v] + 1;
                nxt[u] = (nxt[v] < 0 ? v : nxt[v]);
            }
            else {
                down[u] = down[v] + sub[v];
                sub[v] += sub[u];
                nxt[u] = ~v;
            }
            sub[u] = nsub;
        }

        for (int u = 0; u < n; u++){
            tour[down[u]] = u;
        }

        build_ok = true;
    }

    // down[v] : degree of v
    // nxt[v] : xor prod of neighbor of v
    void build_from_edges(){
        // use tour as queue
        int back = 0;
        for (int u = 0; u < n; u++){
            if (u != root && down[u] == 1){
                tour[back++] = u;
            }
        }
        for (int front = 0; front < n - 1; front++){
            int u = tour[front];
            down[u] = -1;
            int v = nxt[u]; // parent of v
            nxt[v] ^= u;
            if (--down[v] == 1 && v != root){
                tour[back++] = v;
            }
        }
        // check : now, tour is reverse of topological order

        tour.pop_back();

        // check : now, down[*] <= 1
        for (int u : tour){
            int v = nxt[u];
            // subtree size (initialized (1,1,...,1))
            sub[v] += sub[u];
            // heaviest subtree of its child
            down[v] = std::max(down[v], sub[u]);
        }
        for (int u : tour){
            int v = nxt[u];
            // whether u is not the top of heavy path
            if (down[v] == sub[u]){
                sub[u] = ~sub[u];
                down[v] = ~down[v];
            }
        }

        // after appearing v as u (or v == root), 
        // down[v] is the visiting time of euler tour
        // nxt[v] is the lowest vertex of heavy path which contains v
        //   (if v itself, nxt[v] is ~(parent of v))
        // sub[v] + down[v] is the light child's starting time of euler tour
        // note : heavy child's visiting time of euler tour is (the time of its parent) + 1
        sub[root] = ~down[root] + 1;
        down[root] = 0;
        nxt[root] = -1;
        for (int u : tour | std::views::reverse){
            int v = nxt[u];
            int nsub = ~down[u] + 1;
            // heavy child
            if (sub[u] < 0){
                down[u] = down[v] + 1;
                nxt[u] = (nxt[v] < 0 ? v : nxt[v]);
            }
            // light child
            else {
                down[u] = down[v] + sub[v];
                sub[v] += sub[u];
                nxt[u] = ~v;
            }
            sub[u] = nsub;
        }

        // tour is inverse permutation of down
        tour.push_back(root);
        for (int u = 0; u < n; u++){
            tour[down[u]] = u;
        }

        build_ok = true;
    }
};

} // namespace noya2
#line 6 "c26.cpp"

template <class T> struct fenwick_tree {
  public:
    fenwick_tree() : _n(0) {}
    explicit fenwick_tree(int n_) : _n(n_), data(n_) {}

    void add(int p, T x) {
        assert(0 <= p && p < _n);
        p++;
        while (p <= _n) {
            data[p - 1] += x;
            p += p & -p;
        }
    }

    T sum(int l, int r) {
        assert(0 <= l && l <= r && r <= _n);
        return sum(r) - sum(l);
    }

    int _n;
    vector<T> data;

    T sum(int r) {
        T s = 0;
        while (r > 0) {
            s += data[r - 1];
            r -= r & -r;
        }
        return s;
    }
};

ll naive(simple_tree sa, hld_tree b){
    int n = b.size();
    hld_tree a(n);
    rep(v,n) for (int u : sa[v]){
        if (u < v){
            a.add_edge(u,v);
        }
    }
    ll ans = 0;
    rep(v,n){
        auto da = a.dist_table(v);
        auto db = b.dist_table(v);
        rep(u,n){
            ans += (ll)da[u] * db[u];
        }
    }
    return ans;
}



struct range_add_fenwick_tree {
    fenwick_tree<ll> c0, c1;
    range_add_fenwick_tree (int n) : c0(n+1), c1(n+1) {}
    void prefix_apply(int r, ll x){
        c0.add(r, r*x);
        c1.add(r, -x);
    }
    void apply(int l, int r, ll x){
        prefix_apply(r, x);
        prefix_apply(l, -x);
    }
    ll prefix_prod(int r){
        return c0.sum(r) + c1.sum(r) * r;
    }
    ll prod(int l, int r){
        return prefix_prod(r) - prefix_prod(l);
    };
};

struct fast_lca_dist {
    std::vector<int> depth;

};

ll fast(simple_tree a, hld_tree b){
    int n = a.size();
    vector<bool> done(n,false);
    range_add_fenwick_tree depfen(n), distfen(n);
    auto dep = b.dist_table(0);
    // A(u, v) * B(u, v) == (dist[u] + dist[v]) * (dep[u] + dep[v] - 2 * dep[lca(u, v)])
    ll ans = 0;
    for (int ctr : centroid_decomposition(a)){
        done[ctr] = true;
        // numof u, dist[u], dep[u], dist[u]*dep[u]
        ll cnt = 0, distsum = 0, depsum = 0, prdsum = 0;
        auto dfs = [&](auto sfs, int v, int f, int dist) -> void {
            // dist[u] * dep[u]
            ans += prdsum;
            // dist[u] * dep[v]
            ans += distsum * dep[v];
            // dist[v] * dep[u]
            ans += dist * depsum;
            // dist[v] * dep[v]
            ans += dist * dep[v] * cnt;
            // dist[u] * -2dep[lca(u,v)]
            // dist[v] * -2dep[lca(u,v)]
            b.path_query<false>(0, v, [&](int l, int r){
                if (l > r) swap(l, r);
                // return ;
                ans += distfen.prod(l, r) + depfen.prod(l, r) * dist;
            });
            for (int u : a[v]){
                if (done[u]) continue;
                if (u == f) continue;
                sfs(sfs,u,v,dist+1);
            }
        };
        auto efs = [&](auto sfs, int v, int f, int dist) -> void {
            // dist[u] * dep[u]
            prdsum += (ll)dist * dep[v];
            // dist[u] * dep[v]
            distsum += dist;
            // dist[v] * dep[u]
            depsum += dep[v];
            // dist[v] * dep[v]
            cnt += 1;
            // dist[u] * -2dep[lca(u,v)]
            // dist[v] * -2dep[lca(u,v)]
            b.path_query<false>(0, v, [&](int l, int r){
                if (l > r) swap(l, r);
                // return ;
                distfen.apply(l, r, -2 * dist);
                depfen.apply(l, r, -2);
            });
            for (int u : a[v]){
                if (done[u]) continue;
                if (u == f) continue;
                sfs(sfs,u,v,dist+1);
            }
        };
        auto ffs = [&](auto sfs, int v, int f, int dist) -> void {
            // cancel of
            // dist[u] * -2dep[lca(u,v)]
            // dist[v] * -2dep[lca(u,v)]
            b.path_query<false>(0, v, [&](int l, int r){
                if (l > r) swap(l, r);
                // return ;
                distfen.apply(l, r, 2 * dist);
                depfen.apply(l, r, 2);
            });
            for (int u : a[v]){
                if (done[u]) continue;
                if (u == f) continue;
                sfs(sfs,u,v,dist+1);
            }
        };
        // v : ctr
        {
            // dist[u] * dep[u]
            prdsum += 0;
            // dist[u] * dep[v]
            distsum += 0;
            // dist[v] * dep[u]
            depsum += dep[ctr];
            // dist[v] * dep[v]
            cnt += 1;
            // dist[u] * -2dep[lca(u,v)]
            // dist[v] * -2dep[lca(u,v)]
            b.path_query<false>(0, ctr, [&](int l, int r){
                if (l > r) swap(l, r);
                // return ;
                depfen.apply(l, r, -2);
            });
        }
        for (int v : a[ctr]){
            if (done[v]) continue;
            dfs(dfs,v,ctr,1);
            efs(efs,v,ctr,1);
        }
        for (int v : a[ctr]){
            if (done[v]) continue;
            ffs(ffs,v,ctr,1);
        }
        {
            // cancel of
            // dist[u] * -2dep[lca(u,v)]
            // dist[v] * -2dep[lca(u,v)]
            b.path_query<false>(0, ctr, [&](int l, int r){
                if (l > r) swap(l, r);
                // return ;
                depfen.apply(l, r, 2);
            });
        }
    }
    return ans * 2;
}

void solve(){
    int n; in(n);
    simple_tree a(n);
    hld_tree b(n);
    a.input();
    b.input_edges();
    ll ans = fast(a,b);
    out(ans);
    return ;
    ll nans = naive(a,b);
    out(ans,nans); cout << flush;
    assert(ans == nans);
}

int main(){
    int t = 1; //in(t);
    while (t--) { solve(); }
}
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