Merge pull request #780 from AlgorithmWithGod/LiiNi-coder

[20250830] BOJ / G5 / 간선 이어가기 2 / 이인희

Author: ShinHeeEul

LiiNi-coder/202508/30 BOJ 간선 이어가기 2.md

@@ -0,0 +1,81 @@
+```java
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.PriorityQueue;
+import java.util.StringTokenizer;
+import java.util.Arrays;
+
+public class Main {
+	private static BufferedReader br;
+	private static int n, m;
+	private static List<Node>[] graph;
+	private static int[] dist;
+
+	private static class Node implements Comparable<Node> {
+		int v;
+		int w;
+
+		public Node(int v, int w) {
+			this.v = v;
+			this.w = w;
+		}
+
+		@Override
+		public int compareTo(Node o) {
+			return this.w - o.w;
+		}
+	}
+
+	public static void main(String[] args) throws IOException {
+		br = new BufferedReader(new InputStreamReader(System.in));
+		StringTokenizer st = new StringTokenizer(br.readLine());
+		n = Integer.parseInt(st.nextToken());
+		m = Integer.parseInt(st.nextToken());
+		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));
+		}
+		st = new StringTokenizer(br.readLine());
+		int s = Integer.parseInt(st.nextToken());
+		int t = Integer.parseInt(st.nextToken());
+
+		dist = new int[n + 1];
+		Arrays.fill(dist, Integer.MAX_VALUE);
+
+		dijkstra(s);
+		System.out.println(dist[t]);
+	}
+
+	private static void dijkstra(int start) {
+		PriorityQueue<Node> pq = new PriorityQueue<>();
+		dist[start] = 0;
+		pq.add(new Node(start, 0));
+
+		while (!pq.isEmpty()) {
+			Node cur = pq.poll();
+			int v = cur.v;
+			int w = cur.w;
+			if (dist[v] < w)
+                continue;
+			for (Node next : graph[v]) {
+				if (dist[next.v] > dist[v] + next.w) {
+					dist[next.v] = dist[v] + next.w;
+					pq.add(new Node(next.v, dist[next.v]));
+				}
+			}
+		}
+	}
+}
+
+```