제출 #682751

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
682751		NK_	공장들 (JOI14_factories)	C++17	0 / 100	30 ms	12440 KiB

factories

// Success consists of going from failure to failure without loss of enthusiasm
#include <bits/stdc++.h>
#include "factories.h"

using namespace std;

#define nl '\n'

using ll = long long;
using E = array<int, 2>;

const int nax = 5e5+5;
const int LG = 20;
vector<E> adj[nax];
bool vis[nax];
int up[nax][LG];
int par[nax], siz[nax], dep[nax];
ll dx[nax], dy[nax], dst[nax];


const ll INFL = ll(1e18) + 10;

// START OF CENTROID DECOMPOSITION
int find_size(int u, int p = -1) {
	if (vis[u]) return 0;
	siz[u] = 1;
	for(auto e : adj[u]) {
		auto [v, w] = e; 
		if (v == p) continue;
		siz[u] += find_size(v, u);
	}
	return siz[u];
}

int find_centroid(int u, int p, int n) {
	for(auto e : adj[u]) {
		auto [v, w] = e;
		if (v == p) continue;
		if (!vis[v] && siz[v] > n / 2) return find_centroid(v, u, n);
	}
	return u;
}

void init_centroid(int u = 0, int p = -1) {
	find_size(u);

	int c = find_centroid(u, -1, siz[u]);
	vis[c] = 1;
	par[c] = p;
	// cout << c << " -> " << p << endl;

	for(auto e : adj[c]) {
		auto [v, wv] = e;
		if (vis[v]) continue;
		init_centroid(v, c);
	}
}
// END OF CENTROID DECOMPOSITION

// START OF LCA

void dfs(int u = 0, int p = -1) {
	up[u][0] = (p == -1 ? u : p);
	for(int i = 1; i < LG; i++) up[u][i] = up[up[u][i-1]][i-1];

	for(auto e : adj[u]) {
		auto [v, w] = e; 
		if (v == p) continue;
		dst[v] = dst[u] + w;
		dep[v] = dep[u] + 1;
		dfs(v, u);
	}

}

int jmp(int u, int d) {
	for(int i = 0; i < LG; i++) if ((d>>i) & 1) u = up[u][i];
	return u;
}

int lca(int a, int b) {
	if (dep[a] > dep[b]) swap(a, b);
	b = jmp(b, dep[b] - dep[a]); if (a == b) return a;

	for(int i = LG - 1; i >= 0; i--) if (up[a][i] != up[b][i]) a = up[a][i], b = up[b][i];
		
	return up[a][0];
}

int dist(int u, int v) {
	return dst[u] + dst[v] - 2 * dst[lca(u, v)];
}

// END OF LCA

void Init(int N, int A[], int B[], int D[]) {
	for(int i = 0; i < N; i++) {
		vis[i] = 0; par[i] = -1;
		dx[i] = dy[i] = INFL;
		adj[i] = {};
		dst[i] = dep[i] = siz[i] = 0;

		for(int j = 0; j < LG; j++) up[i][j] = 0;
	}

	for(int i = 0; i < N-1; i++) {
		adj[A[i]].push_back({B[i], D[i]});
		adj[B[i]].push_back({A[i], D[i]});
	}

	init_centroid();
	dfs();
}

ll Query(int S, int X[], int T, int Y[]) {
	vector<int> alt;
	for(int i = 0; i < S; i++) {
		int u = X[i]; 
		// cout << u << endl;
		dx[u] = 0; alt.push_back(u);
		while(par[u] != -1) {
			// cout << "PARS: " << u << endl;
			dx[par[u]] = min(dx[par[u]], dx[u] + dist(u, par[u]));
			alt.push_back(u = par[u]);
		}
		// cout << "PARS: " << u << endl;
	}

	for(int i = 0; i < T; i++) {
		int u = Y[i];
		// cout << u << endl;
		dy[u] = 0; alt.push_back(u);
		while(par[u] != -1) {
			// cout << "PART: " << u << endl;
			dy[par[u]] = min(dy[par[u]], dy[u] + dist(u, par[u]));
			alt.push_back(u = par[u]);
		}
		// cout << "PART: " << u << endl;
	}

	sort(begin(alt), end(alt)); alt.erase(unique(begin(alt), end(alt)), end(alt));

	ll ans = INFL;
	for(auto u : alt) {
		// cout << u << " " << dx[u] << " + " << dy[u] << endl;
		ans = min(ans, dx[u] + dy[u]);
		dx[u] = dy[u] = INFL;
	}

	return ans;
}

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