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답안 #532471

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
532471 2022-03-03T01:03:20 Z Pietra 공장들 (JOI14_factories) C++14
100 / 100
 6073 ms 187068 KB 
// tem uma arvore 
// cada companhia produz uma materia smp dif - cada uma tem no minimo
// uma industria, essa ficam nos vertices 
// pode ter mais de uma industria numa msm cidade 
// as vzs uma precisa de material da outra
// queremos minimizar a dist a ser percorrida ao precisar de uma materia da ind G
// query: a companhia u (com empresas em x1, x2,...) precisa
// de material da companhia v (com empresas em y1, y2, ...)
// qual a menor dist?
// lca + centroid 
// pega de um centroid p outro
// guarda o mais prox e p subir do vertice p centroide e de um p outro
// usa o lca pra pegar a dist 
// atualiza o centroid p cada empresa q lê
// vendo se ela cria um novo caminho minimo 
// pega o min entre oq ja ta e o min entre o vertice ate o cara k (centroid)
// na query queremos o minimo de ir ate o centroid atual e a menor 
// dist q ele tem pra algm empresa A 
// lca em o(1) -> lca entre a e b é o cara na euler entre eles com menor nivel 

#include "factories.h"
#include<bits/stdc++.h> 
using namespace std;

const int maxn = 1e6 + 5 ; 
const long long inf = 1e18 ; 
const int maxl = 21 ; 

int n, tab[maxl][maxn], log_[maxn], kra[maxn], dp[maxl][maxn], nivel[maxn], cent[maxn] ; 
long long dist[maxn], resp[maxn], pos[maxn] ; 
int sz[maxn], pai[maxn], timer ;
bool vis[maxn], mark[3*maxn] ; 
int tin[maxn], tout[maxn] ;  
vector<pair<int,int>> grafo[maxn] ; 
vector<int> euler ; 

int minn(int a, int b){return (nivel[a] < nivel[b] ? a : b) ; }

int lca(int u, int v){ 

	int r = max(pos[v], pos[u]), l = min(pos[v], pos[u]) ; 
	int d = log2(r-l+1) ; 

	return minn(dp[d][l], dp[d][r+1-(1<<d)]) ; 

}

long long find_dist(int a, int b){ return dist[a] + dist[b] - ((dist[lca(a, b)])<<1) ; }

void update_cent(int u){

	int k = u ; 

	while(k){
		resp[k] = min(resp[k], find_dist(u, k)) ; 
		k = pai[k] ; 
 	}

}

void ini(int u){

	int k = u ; 

	while(k){ resp[k] = inf ; k = pai[k] ; }

}

long long query(int x){

	int k = x ; long long ans = inf ; 

	while(k){
		if(resp[k] < ans) ans = min(ans, find_dist(x, k) + resp[k]) ; 
		k = pai[k] ; 
	}

	return ans ; 

}

long long Query(int S, int X[], int T, int Y[]) {

	long long ans = inf ; 

	for(int i = 0 ; i < S ; i++) update_cent(X[i]+1) ; 

	for(int i = 0 ; i < T ; i++) ans = min(ans, query(Y[i]+1)) ; 

	for(int i = 0 ; i < S ; i++) ini(X[i]+1) ; 

	return ans ; 

}

void dfs_cent(int v, int p){

	sz[v] = 1 ; 

	for(auto a : grafo[v]){
		if(cent[a.first] || a.first == p) continue ; 
		dfs_cent(a.first, v) ; 
		sz[v] += sz[a.first] ; 
	}

}

int find_cent(int v, int p, int szz){

	for(auto a : grafo[v]){
		if(a.first == p || cent[a.first] || (sz[a.first]<<1) <= szz) continue ;
		return find_cent(a.first, v, szz) ;  
	}

	return v ; 

}

void make_cent(int v, int p){

	dfs_cent(v, p) ; 

	int c = find_cent(v, p, sz[v]) ; 
	cent[c] = 1, pai[c] = p ; 

	for(auto a : grafo[c]){
		if(cent[a.first]) continue ; 
		make_cent(a.first, c) ; 
	}

}

void dfs(int v, int p){

	tin[v] = ++timer ;

	pos[v] = euler.size() ; 
	euler.push_back(v) ;

	for(auto a : grafo[v]){
		if(a.first == p) continue ; 
		nivel[a.first] = nivel[v] + 1 ; dist[a.first] = dist[v] + a.second ; 
		dfs(a.first, v) ; euler.push_back(v) ; 
	}

}

void build(){

	int qtd = euler.size() ; 

	for(int i = 0 ; (1<<i) <= qtd ; i++){
		for(int j = 1 ; j + (1<<i) <= qtd ; j++){
			if(!i) dp[i][j] = euler[j] ;
			else dp[i][j] = minn(dp[i-1][j], dp[i-1][j+(1<<(i-1))]) ;
		}
	}

}

void Init(int N, int A[], int B[], int D[]) {
    
    n = N ; 

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

    euler.push_back(0) ; 
    dfs(1, 0) ; 
    make_cent(1, 0) ; 
    build() ; 

    for(int i = 0 ; i < N + 1 ; i++) resp[i] = inf ; 

}

Subtask #1
15.0 / 15.0

# 결과 실행 시간 메모리 Grader output
1 Correct 23 ms 24452 KB Output is correct
2 Correct 491 ms 34220 KB Output is correct
3 Correct 608 ms 34288 KB Output is correct
4 Correct 557 ms 34244 KB Output is correct
5 Correct 731 ms 34524 KB Output is correct
6 Correct 241 ms 34272 KB Output is correct
7 Correct 612 ms 34244 KB Output is correct
8 Correct 619 ms 34268 KB Output is correct
9 Correct 751 ms 34512 KB Output is correct
10 Correct 267 ms 34208 KB Output is correct
11 Correct 622 ms 34380 KB Output is correct

Subtask #2
18.0 / 18.0

# 결과 실행 시간 메모리 Grader output
1 Correct 14 ms 24140 KB Output is correct
2 Correct 1982 ms 155668 KB Output is correct
3 Correct 2698 ms 158992 KB Output is correct
4 Correct 762 ms 157084 KB Output is correct
5 Correct 3786 ms 187068 KB Output is correct
6 Correct 2860 ms 160108 KB Output is correct
7 Correct 1516 ms 58364 KB Output is correct
8 Correct 409 ms 59020 KB Output is correct
9 Correct 1632 ms 62432 KB Output is correct
10 Correct 1460 ms 59632 KB Output is correct

Subtask #3
67.0 / 67.0

# 결과 실행 시간 메모리 Grader output
1 Correct 23 ms 24452 KB Output is correct
2 Correct 491 ms 34220 KB Output is correct
3 Correct 608 ms 34288 KB Output is correct
4 Correct 557 ms 34244 KB Output is correct
5 Correct 731 ms 34524 KB Output is correct
6 Correct 241 ms 34272 KB Output is correct
7 Correct 612 ms 34244 KB Output is correct
8 Correct 619 ms 34268 KB Output is correct
9 Correct 751 ms 34512 KB Output is correct
10 Correct 267 ms 34208 KB Output is correct
11 Correct 622 ms 34380 KB Output is correct
12 Correct 14 ms 24140 KB Output is correct
13 Correct 1982 ms 155668 KB Output is correct
14 Correct 2698 ms 158992 KB Output is correct
15 Correct 762 ms 157084 KB Output is correct
16 Correct 3786 ms 187068 KB Output is correct
17 Correct 2860 ms 160108 KB Output is correct
18 Correct 1516 ms 58364 KB Output is correct
19 Correct 409 ms 59020 KB Output is correct
20 Correct 1632 ms 62432 KB Output is correct
21 Correct 1460 ms 59632 KB Output is correct
22 Correct 3212 ms 157180 KB Output is correct
23 Correct 2691 ms 159468 KB Output is correct
24 Correct 4624 ms 159812 KB Output is correct
25 Correct 4623 ms 163496 KB Output is correct
26 Correct 4551 ms 160208 KB Output is correct
27 Correct 6073 ms 183400 KB Output is correct
28 Correct 1055 ms 160556 KB Output is correct
29 Correct 4270 ms 159708 KB Output is correct
30 Correct 4216 ms 159384 KB Output is correct
31 Correct 4262 ms 159888 KB Output is correct
32 Correct 1873 ms 63276 KB Output is correct
33 Correct 394 ms 58548 KB Output is correct
34 Correct 1236 ms 55556 KB Output is correct
35 Correct 1250 ms 55668 KB Output is correct
36 Correct 1647 ms 56112 KB Output is correct
37 Correct 1664 ms 56116 KB Output is correct