#654292 (C++17) No.399 動的な領主

• 問題: No.399 動的な領主
• ユーザー: nanophoto12
• 提出日時: 2021-05-05 11:06:43
• 言語: C++17 (gcc 13.3.0 + boost 1.87.0)
• 結果: AC
• 実行時間: 681 ms / 2,000 ms
• コード長: 4,132 bytes
• コンパイル時間: 4,467 ms
• コンパイル使用メモリ: 262,328 KB
• 最終ジャッジ日時: 2025-01-21 07:10:52
• ジャッジサーバーID （参考情報）: judge5 / judge4

ファイルパターン	結果
other	AC * 19

ソースコード

#include <bits/stdc++.h>

#define M_PI       3.14159265358979323846   // pi

using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<ll, ll> P;
typedef tuple<ll, ll, ll> t3;
typedef tuple<ll, ll, ll, ll> t4;

#define rep(a,n) for(ll a = 0;a < n;a++)
#define repi(a,b,n) for(ll a = b;a < n;a++)

#include <bits/stdc++.h>
using namespace std;

template<typename T>
void chmax(T& reference, T value) {
	reference = max(reference, value);
}

template<typename T>
void chmaxmap(map<T, T>& m, T key, T value) {
	if (m.count(key)) {
		chmax(m[key], value);
	}
	else {
		m[key] = value;
	}
}

template<typename T>
void chmin(T& reference, T value) {
	reference = min(reference, value);
}

#include <atcoder/all>

using namespace atcoder;

template< typename G >
struct HeavyLightDecomposition {
    G& g;
    vector< int > sz, in, out, head, rev, par;

    HeavyLightDecomposition(G& g) :
        g(g), sz(g.size()), in(g.size()), out(g.size()), head(g.size()), rev(g.size()), par(g.size()) {}

    void dfs_sz(int idx, int p) {
        par[idx] = p;
        sz[idx] = 1;
        if (g[idx].size() && g[idx][0] == p) swap(g[idx][0], g[idx].back());
        for (auto& to : g[idx]) {
            if (to == p) continue;
            dfs_sz(to, idx);
            sz[idx] += sz[to];
            if (sz[g[idx][0]] < sz[to]) swap(g[idx][0], to);
        }
    }

    void dfs_hld(int idx, int par, int& times) {
        in[idx] = times++;
        rev[in[idx]] = idx;
        for (auto& to : g[idx]) {
            if (to == par) continue;
            head[to] = (g[idx][0] == to ? head[idx] : to);
            dfs_hld(to, idx, times);
        }
        out[idx] = times;
    }

    void build() {
        dfs_sz(0, -1);
        int t = 0;
        dfs_hld(0, -1, t);
    }

    int la(int v, int k) {
        while (1) {
            int u = head[v];
            if (in[v] - k >= in[u]) return rev[in[v] - k];
            k -= in[v] - in[u] + 1;
            v = par[u];
        }
    }

    int lca(int u, int v) {
        for (;; v = par[head[v]]) {
            if (in[u] > in[v]) swap(u, v);
            if (head[u] == head[v]) return u;
        }
    }

    template< typename T, typename Q, typename F >
    T query(int u, int v, const T& ti, const Q& q, const F& f, bool edge = false) {
        T l = ti, r = ti;
        for (;; v = par[head[v]]) {
            if (in[u] > in[v]) swap(u, v), swap(l, r);
            if (head[u] == head[v]) break;
            l = f(q(in[head[v]], in[v] + 1), l);
        }
        return f(f(q(in[u] + edge, in[v] + 1), l), r);
    }

    template< typename Q >
    void add(int u, int v, const Q& q, bool edge = false) {
        for (;; v = par[head[v]]) {
            if (in[u] > in[v]) swap(u, v);
            if (head[u] == head[v]) break;
            q(in[head[v]], in[v] + 1);
        }
        q(in[u] + edge, in[v] + 1);
    }
};

typedef vector<vector<int>> UnWeightedGraph;

struct S {
    long long value;
    int size;
};
using F = long long;

S op(S a, S b) { return { a.value + b.value, a.size + b.size }; }
S e() { return { 0, 0 }; }
S mapping(F f, S x) { return { x.value + f * x.size, x.size }; }
F composition(F f, F g) { return f + g; }
F id() { return 0; }

int main() {
    int n;
    cin >> n;
    vector<vector<int>> g(n);
    rep(i, n - 1) {
        int a, b;
        cin >> a >> b;
        a--; b--;
        g[a].push_back(b);
        g[b].push_back(a);
    }
    HeavyLightDecomposition<UnWeightedGraph> hld(g);
    hld.build();
    lazy_segtree<S, op, e, F, mapping, composition, id> tree(n);
    rep(i, n) tree.set(i, { 0LL, 1 });
    int q;
    cin >> q;
    ll ans = 0;
    rep(i, q) {
        int a, b;
        cin >> a >> b;
        a--; b--;
        ll cost = hld.query(a, b, 0LL, [&](int x, int y) {
            auto p = tree.prod(x, y);
            return p.value + p.size;
            }, [&](ll x, ll y) {
                return x + y;
            });
        //cout << cost << endl;
        ans += cost;
        hld.add(a, b, [&](int x, int y) {
            tree.apply(x, y, 1LL);
            });
    }
    cout << ans << endl;
    return 0;
}