[20251017] BOJ / G4 / 가장 먼 곳 / 이인희

Author: LiiNi-coder

LiiNi-coder/202510/17 BOJ 가장 먼 곳.md

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+```java
+import java.util.*;
+import java.io.*;
+
+class Main {
+
+	static class Node implements Comparable<Node> {
+		int to, weight;
+
+		Node(int to, int weight) {
+			this.to = to;
+			this.weight = weight;
+		}
+
+		@Override
+		public int compareTo(Node o){
+			return this.weight - o.weight;
+		}
+	}
+
+	static int N, M;
+	static List<Node>[] Graph;
+	static int[] Friends = new int[3];
+	static final int INF = Integer.MAX_VALUE;
+
+	public static void main(String[] args) throws IOException {
+		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+		StringTokenizer st;
+
+		N = Integer.parseInt(br.readLine());
+		st = new StringTokenizer(br.readLine());
+		for(int i = 0; i < 3; i++)
+			Friends[i] = Integer.parseInt(st.nextToken());
+
+		M = Integer.parseInt(br.readLine());
+		Graph = new ArrayList[N + 1];
+		for(int i = 1; i <= N; i++)
+			Graph[i] = new ArrayList<>();
+
+		for (int i = 0; i < M; i++) {
+			st = new StringTokenizer(br.readLine());
+			int a = Integer.parseInt(st.nextToken());
+			int b = Integer.parseInt(st.nextToken());
+			int c = Integer.parseInt(st.nextToken());
+			Graph[a].add(new Node(b, c));
+			Graph[b].add(new Node(a, c));
+		}
+
+		int[][] dist = new int[3][N + 1];
+		for(int i = 0; i < 3; i++){
+			dist[i] = dijkstra(Friends[i]);
+		}
+		int answer = 0;
+		int maxMinDist = -1;
+
+		for(int i = 1; i <= N; i++){
+			int minDist = Math.min(dist[0][i], Math.min(dist[1][i], dist[2][i]));
+			if (minDist > maxMinDist) {
+				maxMinDist = minDist;
+				answer = i;
+			}
+		}
+
+
+		System.out.println(answer);
+		br.close();
+	}
+
+	private static int[] dijkstra(int start) {
+		int[] dist = new int[N + 1];
+		Arrays.fill(dist, INF);
+		dist[start] = 0;
+
+		PriorityQueue<Node> pq = new PriorityQueue<>();
+		pq.offer(new Node(start, 0));
+		while(!pq.isEmpty()){
+			Node cur = pq.poll();
+			if(cur.weight > dist[cur.to])
+				continue;
+
+			for(Node next : Graph[cur.to]){
+				int cost = cur.weight + next.weight;
+				if(cost < dist[next.to]){
+					dist[next.to] = cost;
+					pq.offer(new Node(next.to, cost));
+				}
+			}
+		}
+		return dist;
+	}
+}
+
+```