[20251227] BOJ / G4 / 해킹 / 김민진

zinnnn37/202512/27 BOJ G4 해킹.md

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+```java
+import java.io.*;
+import java.util.*;
+
+public class BJ_10282_해킹 {
+
+    private static final BufferedReader  br = new BufferedReader(new InputStreamReader(System.in));
+    private static final BufferedWriter  bw = new BufferedWriter(new OutputStreamWriter(System.out));
+    private static final StringBuilder   sb = new StringBuilder();
+    private static       StringTokenizer st;
+
+    private static int N, D, C;
+    private static int[]        dist;
+    private static Queue<Node>  pq;
+    private static List<Node>[] graph;
+
+    private static class Node implements Comparable<Node> {
+        int to;
+        int weight;
+
+        Node(int to, int weight) {
+            this.to = to;
+            this.weight = weight;
+        }
+
+        @Override
+        public int compareTo(Node o) {
+            return Integer.compare(this.weight, o.weight);
+        }
+
+    }
+
+    public static void main(String[] args) throws IOException {
+        int T = Integer.parseInt(br.readLine());
+
+        while (T-- > 0) {
+            init();
+            sol();
+        }
+        bw.write(sb.toString());
+        bw.flush();
+        bw.close();
+        br.close();
+    }
+
+    private static void init() throws IOException {
+        st = new StringTokenizer(br.readLine());
+        N = Integer.parseInt(st.nextToken());
+        D = Integer.parseInt(st.nextToken());
+        C = Integer.parseInt(st.nextToken());
+
+        graph = new List[N + 1];
+        for (int i = 1; i <= N; i++) {
+            graph[i] = new ArrayList<>();
+        }
+
+        dist = new int[N + 1];
+        Arrays.fill(dist, Integer.MAX_VALUE);
+
+        pq = new PriorityQueue<>();
+        for (int i = 0; i < D; i++) {
+            st = new StringTokenizer(br.readLine());
+
+            int a = Integer.parseInt(st.nextToken());
+            int b = Integer.parseInt(st.nextToken());
+            int s = Integer.parseInt(st.nextToken());
+
+            graph[b].add(new Node(a, s));
+        }
+
+    }
+
+    private static void sol() throws IOException {
+        pq.offer(new Node(C, 0));
+        dist[C] = 0;
+
+        while (!pq.isEmpty()) {
+            Node cur = pq.poll();
+
+            if (cur.weight > dist[cur.to]) continue;
+
+            for (Node next : graph[cur.to]) {
+                int nextWeight = dist[cur.to] + next.weight;
+
+                if (dist[next.to] > nextWeight) {
+                    dist[next.to] = nextWeight;
+                    pq.offer(new Node(next.to, nextWeight));
+                }
+            }
+        }
+
+        int cnt = 0;
+        int max = 0;
+        for (int i = 1; i <= N; i++) {
+            if (dist[i] == Integer.MAX_VALUE) continue;
+
+            cnt++;
+            max = Math.max(max, dist[i]);
+        }
+        sb.append(cnt).append(" ").append(max).append("\n");
+    }
+
+}
+```