結果

問題 No.898 tri-βutree
コンテスト
ユーザー kcvlex
提出日時 2019-10-05 01:46:02
言語 C++14
(gcc 13.3.0 + boost 1.87.0)
結果
AC  
実行時間 487 ms / 4,000 ms
コード長 5,020 bytes
コンパイル時間 1,889 ms
コンパイル使用メモリ 184,548 KB
実行使用メモリ 57,984 KB
最終ジャッジ日時 2024-11-08 22:45:02
合計ジャッジ時間 11,033 ms
ジャッジサーバーID
（参考情報） 		judge4 / judge3
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 * 1
other AC * 21
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 # 

// #define DEBUGGING
#include <bits/stdc++.h>
using namespace std;
#define endl '\n'
#define ALL(V) (V).begin(), (V).end()
#define ALLR(V) (V).rbegin(), (V).rend()

template <typename T> using V = vector<T>;
template <typename T> using VV = V<V<T>>;
using ll = int64_t;
using ull = uint64_t;
using PLL = pair<ll, ll>;

template <typename T> const T& var_min(const T &t) { return t; }
template <typename T> const T& var_max(const T &t) { return t; }
template <typename T, typename... Tail> const T& var_min(const T &t, const Tail&... tail) { return min(t, var_min(tail...)); }
template <typename T, typename... Tail> const T& var_max(const T &t, const Tail&... tail) { return max(t, var_max(tail...)); }
template <typename T, typename... Tail> void chmin(T &t, const Tail&... tail) { t = var_min(t, tail...); }
template <typename T, typename... Tail> void chmax(T &t, const Tail&... tail) { t = var_max(t, tail...); }
template <typename T> const T& clamp(const T &t, const T &low, const T &high) { return max(low, min(high, t)); }
template <typename T> void chclamp(T &t, const T &low, const T &high) { t = clamp(t, low, high); }

namespace init__ {

struct InitIO {
    InitIO() {
        cin.tie(nullptr);
        ios_base::sync_with_stdio(false);
        cout << fixed << setprecision(30);
    }
} init_io;

}

#ifdef DEBUGGING
// #include "../debug/debug.cpp"
#include "../../debug/debug.cpp"
#else
#define DEBUG(...) 0
#define DEBUG_SEPARATOR_LINE 0
#endif

template <typename T>
T make_v(T init) { return init; }

template <typename T, typename... Tail>
auto make_v(T init, size_t s, Tail... tail) {
#define rec make_v(init, tail...)
    return V<decltype(rec)>(s, rec);
#undef rec
}

template <size_t Size = 30>
class Lca {
    const ll nopt;
    ll N;
    ll root;
    V<ll> depth;
    VV<ll> edge;
    VV<ll> parents;

    void dfs(ll now, ll pre, ll d) {
        parents[now][0] = pre;
        depth[now] = d;
        for(ll next : edge[now]) {
            if(next != pre) {
                dfs(next, now, d + 1);
            }
        }
    }

public:
    Lca(ll N, ll root, const vector<vector<ll>> &e)
        : nopt(-1),
          N(N),
          root(root),
          edge(e),
          parents(N, V<ll>(Size))
    {
        depth.resize((size_t)N);
        dfs(root, nopt, 0);

        for(ll i = 1; i < Size; i++) {
            for(ll node = 0; node < N; node++) {
                if(parents[node][i - 1] == nopt) {
                    parents[node][i] = nopt;
                } else {
                    parents[node][i] = parents[parents[node][i - 1]][i - 1];
                }
            }
        }
    }

    Lca(ll n, const vector<vector<ll>> &e) : Lca(n, 0, e) 
    {
    }

    ll get_depth(ll node) { return depth[node]; }

    ll get_parents(ll node, ll relative_depth) {
        ll ret = node;
        for(ll i = 0; (1 << i) <= relative_depth && ret != -1; i++) {
            if(relative_depth & (1 << i)) {
                ret = parents[ret][i];
            }
        }
        return ret;
    }

    ll get_lca(ll n1, ll n2) {
        ll d = min(depth[n1], depth[n2]);
        ll ok = 0, ng = d + 1;
        ll ret = 0;
        while(abs(ok - ng) > 1) {
            ll mid = (ok + ng) / 2;
            ll p1 = get_parents(n1, depth[n1] - mid);
            ll p2 = get_parents(n2, depth[n2] - mid);
            if(p1 == p2) {
                ok = mid;
                ret = p1;
            } else {
                ng = mid;
            }
        }
        return ret;
    }
};

void calc_wd(ll cur, ll pre, const VV<PLL> &edges, V<ll> &weight, ll cur_weight) {
    weight[cur] = cur_weight;
    for(auto &&edge : edges[cur]) {
        ll nxt, cost;
        tie(nxt, cost) = edge;
        if(nxt == pre) continue;
        calc_wd(nxt, cur, edges, weight, cur_weight + cost);
    }
}

int main() {
    ll N;
    cin >> N;
    VV<PLL> wedges(N);
    VV<ll> edges(N);
    
    {
        auto add_edge = [&](ll u, ll v, ll w) {
            wedges[u].emplace_back(v, w);
            edges[u].push_back(v);
        };

        for(ll i = 1; i < N; i++) {
            ll u, v, w;
            cin >> u >> v >> w;
            add_edge(u, v, w);
            add_edge(v, u, w);
        }
    }

    V<ll> weight(N);
    calc_wd(0, -1, wedges, weight, 0);
    Lca<30> lca(N, 0, edges);

    ll Q;
    cin >> Q;
    ll xyz[3];
    while(Q--) {
        DEBUG(Q);
        for(ll i = 0; i < 3; i++) cin >> xyz[i];
        sort(xyz, xyz + 3);
        ll ans = 5e15;
        do {
            ll cost = 0;
            ll cur_lca = xyz[0];
            for(ll i = 1; i <= 2; i++) {
                ll nxt_lca = lca.get_lca(cur_lca, xyz[i]);
                DEBUG(make_tuple(cur_lca, nxt_lca, xyz[i], weight[cur_lca], weight[xyz[i]], weight[nxt_lca]));
                cost += weight[cur_lca] + weight[xyz[i]] - 2 * weight[nxt_lca];
                cur_lca = nxt_lca;
            }
            chmin(ans, cost);
        } while(next_permutation(xyz, xyz + 3));
        cout << ans << endl;
    }
    return 0;
}
0