Submission #908180

#	Time	Username	Problem	Language	Result	Execution time	Memory
908180		typ_ik	Factories (JOI14_factories)	C++17	15 / 100	8038 ms	147544 KiB

factories

#include <bits/stdc++.h>
#include "factories.h"

#define ll long long
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define watch(x) cout << (#x) << " : " << x << '\n'
#define boost ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);

using namespace std; 

const int N = 5e5 + 128;
const ll INF = 1e15 + 128;
const int LOG = 19;
int lift[N][LOG], depth[N];
ll d[N];
vector < pair<int, int> > g[N];
int n, q;
bool was[N];
int h[N]; 
ll res[N];

void init(int v, ll val = 0, int p = 1) {
    d[v] = val;

    if (v != 1)
        depth[v] = depth[p] + 1;

    lift[v][0] = p;
    for (int b = 1; b < LOG; b++)
        lift[v][b] = lift[lift[v][b-1]][b-1];

    for (auto& [to, len] : g[v])
        if (to != p)
            init(to, val+len, v);
}

int lca(int u, int v) {
    if (depth[u] < depth[v])
        swap(u, v);
    int k = depth[u] - depth[v];
    for (int b = 0; b < LOG; b++)
        if ((k >> b) & 1)
            u = lift[u][b];
    if (u == v)
        return u;
    for (int b = LOG - 1; b >= 0; b--)
        if (lift[v][b] != lift[u][b])
            v = lift[v][b], u = lift[u][b];
    return lift[v][0];
}

ll get(int u, int v) {
    return d[u]+d[v]-2*d[lca(u,v)];
}

void dfs(int v, int p = -1) {
    h[v] = 1;   

    for (auto& [to, len] : g[v])
        if (to != p && !was[to])
            dfs(to, v), h[v] += h[to];
} 

int find_centroid(int v, int p, int sz) { 
    for (auto& [to, len] : g[v])
        if (to != p && h[to] > sz / 2 && !was[to])
            return find_centroid(to, v, sz);
    return v;
}

int p[N];

void decompose(int v, int pr = -1) { 
    dfs(v); 

    int c = find_centroid(v, -1, h[v]);   

    p[c] = pr;
    was[c] = true;

    for (auto& [to, len] : g[c])
        if (!was[to])
            decompose(to, c);
}

void update(int v) {
    int c = v;
    while (c != -1) 
        res[c] = min(res[c], get(c, v)), c = p[c];
}

void reset(int v) {
    int c = v;
    while (c != -1) 
        res[c] = INF, c = p[c]; 
}

ll get(int v) {
    ll ans = INF;
    int c = v;
    while (c != -1)
        ans = min(ans, get(c,v)+res[c]), c = p[c];
    return ans;
}

void Init(int N, int A[], int B[], int D[]) {
    n = N;
    for (int i = 0; i + 1 < n; i++) {
        int u = A[i], v = B[i], w = D[i];
        g[u].push_back(make_pair(v, w));
        g[v].push_back(make_pair(u, w));
    }
    for (int i = 0; i <= n; i++)
        res[i] = INF, p[i] = -1;
    decompose(1);
    init(1);
}

long long Query(int S, int X[], int T, int Y[]) {
    for (int i = 0; i < S; i++)
        update(X[i]);
    ll tot = INF;
    for (int i = 0; i < T; i++)
        tot = min(tot, get(Y[i]));
    for (int i = 0; i < S; i++)
        reset(X[i]);
    return tot;
}   

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