제출 #860989

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
860989		12345678	Harbingers (CEOI09_harbingers)	C++17	50 / 100	69 ms	17872 KiB

harbingers

#include <bits/stdc++.h>

using namespace std;

#define ll long long

const ll nx=1e5+5, inf=1e18;
ll n, ds[nx], lz[nx], sp[nx], ans[nx], u, v, w;
vector<pair<int, int>> d[nx];
bool querymode;

struct line
{
    ll m, c;
    mutable ll p;
    line(ll m, ll c, ll p): m(m), c(c), p(p){}
    bool operator< (const line &o) const {return querymode?p<o.p:m>o.m;}
};

struct convexhull:multiset<line>
{
    ll div(ll a, ll b)
    {
        if (a%b==0||(a^b)>=0) return a/b;
        return a/b-1;
    }
    bool isect(iterator x, iterator y)
    {
        if (y==end()) return x->p=inf, false;
        if (x->m==y->m) x->p=x->m>=y->m?-inf:inf;
        else x->p=div(y->c-x->c, x->m-y->m);
        return x->p>=y->p;
    }
    void add(ll m, ll c)
    {
        auto x=insert(line(m, c, 0)), y=next(x);
        while (isect(x, y)) y=erase(y);
        if ((y=x)!=begin()&&isect(--x, y)) isect(x, erase(y));
        while ((y=x)!=begin()&&(--x)->p>=y->p) isect(x, erase(y));
    }
    ll query(ll x)
    {
        querymode=1;
        auto itr=lower_bound(line(0, 0, x));
        querymode=0;
        return itr->m*x+itr->c;
    }
} s;

void pre(int u, int p)
{
    for (auto [v, w]:d[u]) if (v!=p) ds[v]=ds[u]+w, pre(v, u);
}

void dfs(int u, int p)
{
    if (u!=1) ans[u]=lz[u]+ds[u]*sp[u]+s.query(sp[u]);
    s.add(-ds[u], ans[u]);
    for (auto [v, w]:d[u]) if (v!=p) dfs(v, u);
}

int main()
{
    cin.tie(NULL)->sync_with_stdio(false);
    cin>>n;
    for (int i=0; i<n-1; i++) cin>>u>>v>>w, d[u].push_back({v, w}), d[v].push_back({u, w});
    for (int i=2; i<=n; i++) cin>>lz[i]>>sp[i];
    pre(1, 1); dfs(1, 1);
    for (int i=2; i<=n; i++) cout<<ans[i]<<'\n';
}

• Subtask 1: 50 / 100