1+ import java .util .*;
2+ 3+ class Solution {
4+ 5+ static int N ;
6+ static List <Node >[] g ;
7+ static Set <Integer > gSet ;
8+ static Set <Integer > sSet ;
9+ static PriorityQueue <int []> pq ;
10+ static class Node {
11+ int edge , cost ;
12+ public Node (int edge , int cost ) {
13+ this .edge = edge ;
14+ this .cost = cost ;
15+ }
16+ }
17+ 18+ public int [] solution (int n , int [][] paths , int [] gates , int [] summits ) {
19+ N = n ;
20+ g = new ArrayList [N +1 ];
21+ for (int i =1 ; i <N +1 ; i ++) {
22+ g [i ] = new ArrayList <>();
23+ }
24+ 25+ for (int i =0 ; i <paths .length ; i ++) {
26+ int [] p = paths [i ];
27+ g [p [0 ]].add (new Node (p [1 ], p [2 ]));
28+ g [p [1 ]].add (new Node (p [0 ], p [2 ]));
29+ }
30+ 31+ gSet = new HashSet <>();
32+ for (int gate : gates ) {
33+ gSet .add (gate );
34+ }
35+ sSet = new HashSet <>();
36+ for (int summit : summits ) {
37+ sSet .add (summit );
38+ }
39+ 40+ pq = new PriorityQueue <>((o1 , o2 ) -> o1 [1 ]==o2 [1 ] ? o1 [0 ]-o2 [0 ] :o1 [1 ]-o2 [1 ]);
41+ 42+ // 산봉우리를 시작점으로 bfs
43+ for (int summit : summits ) {
44+ bfs (summit );
45+ }
46+ 47+ int [] answer = pq .poll ();
48+ 49+ return answer ;
50+ }
51+ public static void bfs (int start ) {
52+ // 큐를 우선순위 큐로 설정하여, 비용이 작은 순부터 우선 탐색하도록 함
53+ PriorityQueue <int []> q = new PriorityQueue <>((o1 , o2 )-> o1 [0 ]-o2 [0 ]);
54+ boolean [] visited = new boolean [N +1 ];
55+ 56+ // {비용, 노드}
57+ q .add (new int [] {0 , start });
58+ visited [start ] = true ;
59+ 60+ int intensity = Integer .MAX_VALUE ;
61+ while (!q .isEmpty ()) {
62+ int [] now = q .poll ();
63+ 64+ // 출입구를 만남
65+ if (gSet .contains (now [1 ])) {
66+ pq .add (new int [] {start , now [0 ]});
67+ break ;
68+ }
69+ 70+ // 등산로 반복
71+ for (Node next : g [now [1 ]]) {
72+ if (sSet .contains (next .edge )) continue ;
73+ if (visited [next .edge ]) continue ;
74+ 75+ visited [now [1 ]] = true ;
76+ int max = Math .max (now [0 ], next .cost );
77+ q .add (new int [] {max , next .edge });
78+ }
79+ }
80+ }
81+ }
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