제출 #880245

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
880245		DylanSmith	Harbingers (CEOI09_harbingers)	C++17	30 / 100	101 ms	42240 KiB

harbingers

#include <bits/stdc++.h>

using namespace std;

typedef long long ll;

#define pb push_back
#define sz(x) (int)x.size()
#define all(x) begin(x),end(x)
#define lb(x,y) lower_bound(all(x),y)-begin(x)

mt19937 rng;

struct Line {
    mutable ll k, m, p;
    bool operator<(const Line& o) const { return k < o.k; }
    bool operator<(ll x) const { return p < x; }
};

struct LineContainer : multiset<Line, less<>> {
    // (for doubles, use inf = 1/.0, div(a,b) = a/b)
    static const ll inf = LLONG_MAX;
    ll div(ll a, ll b) { // floored division
        return a / b - ((a ^ b) < 0 && a % b); }
    stack<Line> st; stack<int> type;
    int getTime() { return sz(type); }
    void setTime(int t) {
        while (sz(type) > t) {
            int t = type.top(); type.pop();
            Line p = st.top(); st.pop();
            if (t == 0) {
                insert(p);
            } else if (t == 1) {
                erase(p);
            } else {
                Line q = st.top(); st.pop();
                lower_bound(p)->p = q.p;
            }
        }
    }
    bool isect(iterator x, iterator y) {
        if (y == end()) return x->p = inf, 0;
        if (x->k == y->k) x->p = x->m > y->m ? inf : -inf;
        else x->p = div(y->m - x->m, x->k - y->k);
        return x->p >= y->p;
    }
    bool isectR(iterator x, iterator y) {
        st.push(*x);
        bool res = isect(x, y);
        type.push(2); st.push(*x);
        return res;
    }
    iterator eraseR(iterator x) {
        type.push(0);
        st.push(*x);
        return erase(x);
    }
    void add(ll k, ll m) {
        type.push(1);
        st.push({k, m, 0});
        auto z = insert({k, m, 0}), y = z++, x = y;
        while (isectR(y, z)) z = eraseR(z);
        if (x != begin() && isectR(--x, y)) isectR(x, y = eraseR(y));
        while ((y = x) != begin() && (--x)->p >= y->p)
            isectR(x, eraseR(y));
    }
    ll query(ll x) {
        assert(!empty());
        auto l = *lower_bound(x);
        return l.k * x + l.m;
    }
};

vector<vector<int>> adj;
vector<ll> p;
LineContainer lc;
vector<ll> res;
vector<int> s, v;
void dfs(int u) {
    if (u > 0) {
        res[u] = -lc.query(v[u]) + s[u] + (ll)v[u] * p[u];
        lc.add(p[u], -res[u]);
    }
    for (int v : adj[u]) {
        int t = lc.getTime();
        dfs(v);
        //lc.setTime(t);
    }
}

void solve() {
    int N; cin >> N;
    adj = vector<vector<int>>(N);
    vector<vector<int>> edges;
    for (int i = 0; i < N - 1; i++) {
        int u, v, k; cin >> u >> v >> k; u--; v--;
        edges.pb({u, v, k});
        adj[u].pb(v);
        adj[v].pb(u);
    }
    s = vector<int>(N);
    v = vector<int>(N);
    for (int i = 1; i < sz(s); i++) cin >> s[i] >> v[i];
    queue<int> q;
    q.push(0);
    vector<int> depth(N, 0);
    vector<int> srt;
    while (!q.empty()) {
        int u = q.front(); q.pop();
        srt.pb(u);
        for (int v : adj[u]) {
            adj[v].erase(find(all(adj[v]), u));
            depth[v] = depth[u] + 1;
            q.push(v);
        }
    }
    p = vector<ll>(N, 0);
    for (auto &edge : edges) {
        int u = edge[0], v = edge[1], k = edge[2];
        if (depth[v] > depth[u]) swap(u, v);
        p[u] = k;
    }
    for (int u : srt) {
        for (int v : adj[u]) p[v] += p[u];
    }
    lc.add(0, 0);
    res = vector<ll>(N);
    dfs(0);
    for (int i = 1; i < sz(res); i++) {
        cout << res[i] << (i == sz(res) - 1 ? "\n" : " ");
    }
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    rng = mt19937(chrono::steady_clock::now().time_since_epoch().count());

    solve();

    return 0;
}

컴파일 시 표준 에러 (stderr) 메시지

harbingers.cpp: In function 'void dfs(int)':
harbingers.cpp:86:13: warning: unused variable 't' [-Wunused-variable]
   86 |         int t = lc.getTime();
      |             ^

• Subtask 1: 30 / 100