Submission #387685

#	Time	Username	Problem	Language	Result	Execution time	Memory
387685		arujbansal	Factories (JOI14_factories)	C++17	Compilation error	0 ms	0 KiB

factories

#include "factories.h"

#include <iostream>
#include <algorithm>
#include <vector>
#include <map>
#include <set>
#include <array>
#include <stack>
#include <queue>
#include <random>
#include <numeric>
#include <functional>
#include <chrono>
#include <utility>
#include <iomanip>
#include <assert.h>

using namespace std;

void dbg_out() { cerr << endl; }
template<typename Head, typename... Tail>
void dbg_out(Head H, Tail... T) { cerr << ' ' << H; dbg_out(T...); }
#define dbg(...) cerr << "(" << #__VA_ARGS__ << "):", dbg_out(__VA_ARGS__)

#define rng_init mt19937 rng(chrono::steady_clock::now().time_since_epoch().count())
#define rng_seed(x) mt19937 rng(x)
#define all(x) (x).begin(), (x).end()
#define sz(x) (int) (x).size()
// #define int long long

using ll = long long;

const int MXN = 5e5 + 5, MXK = 19;
const ll INF = 1e18;
vector<pair<int, ll>> g[MXN];
int cd_par[MXN], binlift_par[MXN][MXK], tin[MXN], tout[MXN], subtree[MXN];
ll binlift_dist[MXN][MXK], best[MXN];
bool vis[MXN];
int timer;

void dfs1(int u, int p) {
    tin[u] = timer++;

    for (int j = 1; j < MXK; j++) {
        binlift_par[u][j] = binlift_par[binlift_par[u][j - 1]][j - 1];
        binlift_dist[u][j] = binlift_dist[u][j - 1] + binlift_dist[binlift_par[u][j - 1]][j - 1];
    }

    for (const auto &[v, w] : g[u]) {
        if (v == p) continue;

        binlift_par[v][0] = u;
        binlift_dist[v][0] = w;

        dfs1(v, u);
    }

    tout[u] = timer - 1;
}

bool is_anc(int u, int v) { return tin[u] <= tin[v] && tout[u] >= tout[v]; }

int query_lca(int u, int v) {
    if (is_anc(u, v)) return u;
    if (is_anc(v, u)) return v;

    for (int j = MXK - 1; j >= 0; j--) {
        int lift = binlift_par[u][j];

        if (!is_anc(lift, v))
            u = lift;
    }

    return binlift_par[u][0];
}

int query_dist(int u, int v) {
    if (u == v) return 0;

    ll res = 0;

    for (int j = MXK - 1; j >= 0; j--) {
        int lift = binlift_par[u][j];

        if (!is_anc(lift, v)) {
            res += binlift_dist[u][j];
            u = lift;
        }
    }

    return res + binlift_dist[u][0];
}

ll dist(int u, int v) {
    if (u == v) return 0;
    int cur_lca = query_lca(u, v);
    return query_dist(u, cur_lca) + query_dist(v, cur_lca);
}

void dfs_subtree(int u, int p) {
    subtree[u] = 1;

    for (const auto &[v, w] : g[u]) {
        if (v == p || vis[v]) continue;

        dfs_subtree(v, u);
        subtree[u] += subtree[v];
    }
}

int centroid(int u, int p, int vertices) {
    for (const auto &[v, w] : g[u]) {
        if (v == p || vis[v]) continue;

        if (subtree[v] * 2 > vertices)
            return centroid(v, u, vertices);
    }

    return u;
}

void build_cd(int u, int p) {
    dfs_subtree(u, -1);
    int c = centroid(u, -1, subtree[u]);

    if (p == -1)
        p = c;

    cd_par[c] = p;
    vis[c] = true;

    for (const auto &[v, w] : g[c]) {
        if (vis[v]) continue;
        build_cd(v, c);
    }
}

void build_factory(int u) {
    int v = u;
    best[v] = 0;

    do {
        v = cd_par[v];
        best[v] = min(best[v], dist(u, v));
    } while (v != cd_par[v]);
}

void remove_factory(int v) {
    best[v] = INF;

    do {
        v = cd_par[v];
        best[v] = INF;
    } while (v != cd_par[v]);
}

ll query_factory(int u) {
    int v = u;
    ll ans = best[v];

    do {
        v = cd_par[v];
        ans = min(ans, dist(u, v) + best[v]);
    } while (v != cd_par[v]);

    return ans;
}

void init(int N, vector<int> A, vector<int> B, vector<int> D) {
    for (int i = 0; i < N - 1; i++) {
        g[A[i]].emplace_back(B[i], D[i]);
        g[B[i]].emplace_back(A[i], D[i]);
    }

    dfs1(0, -1);
    build_cd(0, -1);

    for (int i = 1; i <= N; i++)
        best[i] = INF;
}

ll query(int S, vector<int> X, int T, vector<int> Y) {
    ll ans = INF;

    for (const auto &v : X)
        build_factory(v);

    for (const auto &v : Y)
        ans = min(ans, query_factory(v));

    for (const auto &v : X)
        remove_factory(v);

    return ans;
}

// void solve() {
//     int N,  Q;
//     cin >> N >> Q;

//     vector<int> A(N - 1), B(N - 1), D(N - 1);
//     for (int i = 0; i < N - 1; i++)
//         cin >> A[i] >> B[i] >> D[i];

//     Init(N, A, B, D);

//     while (Q--) {
//         int S, T;
//         cin >> S >> T;

//         vector<int> X(S), Y(T);
//         for (auto &x : X) cin >> x;
//         for (auto &x : Y) cin >> x;

//         cout << Query(S, X, T, Y) << "\n";
//     }

//     // for (int i = 0; i < N; i++) {
//     //     for (int j = i + 1; j < N; j++) {
//     //         dbg(i, j, dist(i, j));
//     //     }
//     // }

//     // dbg(query_lca(5, 6), query_dist(5, 1));

//     // for (int j = 0; j < MXK; j++)
//     //     dbg(j, binlift_dist[5][j]);
// }

// signed main() {
//     ios_base::sync_with_stdio(false);
//     cin.tie(nullptr);

//     int TC = 1;
//     // cin >> TC;
//     while (TC--) solve();
// }

Compilation message (stderr)

/tmp/cc0jBOfX.o: In function `main':
grader.cpp:(.text.startup+0x37b): undefined reference to `Init(int, int*, int*, int*)'
grader.cpp:(.text.startup+0x412): undefined reference to `Query(int, int*, int, int*)'
collect2: error: ld returned 1 exit status