Submission #413438

#	Time	Username	Problem	Language	Result	Execution time	Memory
413438		souvenir_vayne	Factories (JOI14_factories)	C++14	0 / 100	20 ms	24140 KiB

factories

#include <bits/stdc++.h>
#include "factories.h"
#define pb push_back
#define LINF 0x3f3f3f3f3f3f3f3f
#define endl '\n'
#define ll long long
#define f first
#define s second
using namespace std;
typedef pair<int, ll> pii;

const int MAXN = 5e5+5;

int sz[MAXN], used[MAXN];
ll best[MAXN];
vector<pii> g[MAXN], ng[MAXN];

int getsz(int u, int p) {
    sz[u] = 1;
    for(pii &i : g[u])
        if(i.f != p && !used[i.f])
            sz[u] += getsz(i.f, u);
    return sz[u];
}

int findc(int u, int p, int n) {
    for(pii &i : g[u])
        if(i.f != p && !used[i.f] && sz[i.f] > n/2)
            return findc(i.f, u, n);
    return u;
}

void getng(int u, int p, int c, ll dist) {
    if(u != c)
        ng[u].pb({c, dist});
    for(pii &i : g[u])
        if(i.f != p && !used[i.f])
            getng(i.f, u, c, dist + i.s);
}

void build(int u, int p) {

    int c = findc(u, -1, getsz(u, -1));
    getng(c, -1, c, 0);
    used[c] = 1;

    for(pii &i : g[c])
        if(!used[i.f])
            build(i.f, c);
}

void Init(int n, int a[], int b[], int c[]) {
    for(int i = 0; i < n; i++)
        best[i] = LINF;

    for(int i = 0; i < n-1; i++) {
        g[a[i]].pb({b[i], c[i]});
        g[b[i]].pb({a[i], c[i]});
    }

    build(0, -1);
}

ll Query(int s, int x[], int t, int y[]) {

    ll ans = LINF;
    for(int u = 0; u < s; u++)
        for(pii &i : ng[u])
            best[i.f] = min(best[i.f], i.s);
    for(int u = 0; u < t; u++)
        for(pii &i : ng[u])
            ans = min(ans, best[i.f] + i.s);
    for(int u = 0; u < s; u++)
        for(pii &i : ng[u])
            best[i.f] = LINF;

    return ans;
}

• Subtask 1: 0 / 15
• Subtask 2: 0 / 18
• Subtask 3: 0 / 67