[20251027] BOJ / G4 / 서강그라운드 / 김민진

zinnnn37/202510/27 BOJ G4 서강그라운드.md

@@ -0,0 +1,112 @@
+```java
+import java.io.*;
+import java.util.*;
+
+public class BJ_14938_서강그라운드 {
+
+	private static final BufferedReader  br = new BufferedReader(new InputStreamReader(System.in));
+	private static final BufferedWriter  bw = new BufferedWriter(new OutputStreamWriter(System.out));
+	private static       StringTokenizer st;
+
+	private static int N, M, R, tmp, ans;
+	private static int[] dist, vals;
+	private static List<Node>[] graph;
+	private static Queue<Node>  q;
+
+	private static class Node implements Comparable<Node> {
+		int to;
+		int dist;
+
+		public Node(int to, int dist) {
+			this.to = to;
+			this.dist = dist;
+		}
+
+		@Override
+		public int compareTo(Node o) {
+			return Integer.compare(this.dist, o.dist);
+		}
+	}
+
+	public static void main(String[] args) throws IOException {
+		init();
+		sol();
+	}
+
+	private static void init() throws IOException {
+		st = new StringTokenizer(br.readLine());
+
+		N = Integer.parseInt(st.nextToken());
+		M = Integer.parseInt(st.nextToken());
+		R = Integer.parseInt(st.nextToken());
+
+		ans = 0;
+		vals = new int[N + 1];
+		st = new StringTokenizer(br.readLine());
+		for (int i = 1; i <= N; i++) {
+			vals[i] = Integer.parseInt(st.nextToken());
+		}
+
+		graph = new List[N + 1];
+		for (int i = 1; i <= N; i++) {
+			graph[i] = new ArrayList<>();
+		}
+
+		for (int i = 0; i < R; i++) {
+			st = new StringTokenizer(br.readLine());
+
+			int u = Integer.parseInt(st.nextToken());
+			int v = Integer.parseInt(st.nextToken());
+			int w = Integer.parseInt(st.nextToken());
+
+			graph[u].add(new Node(v, w));
+			graph[v].add(new Node(u, w));
+		}
+
+		q = new PriorityQueue<>();
+		dist = new int[N + 1];
+	}
+
+	private static void sol() throws IOException {
+		for (int i = 1; i <= N; i++) {
+			dijkstra(i);
+
+			tmp = 0;
+			for (int j = 1; j <= N; j++) {
+				if (dist[j] <= M) {
+					tmp += vals[j];
+				}
+			}
+			ans = Math.max(ans, tmp);
+		}
+		bw.write(ans + "\n");
+		bw.flush();
+		bw.close();
+		br.close();
+	}
+
+	private static void dijkstra(int start) {
+		q.clear();
+		Arrays.fill(dist, Integer.MAX_VALUE);
+		dist[start] = 0;
+
+		q.offer(new Node(start, 0));
+
+		while (!q.isEmpty()) {
+			Node cur = q.poll();
+
+			if (dist[cur.to] < cur.dist) continue;
+
+			for (Node next : graph[cur.to]) {
+				int newDist = dist[cur.to] + next.dist;
+
+				if (newDist < dist[next.to]) {
+					dist[next.to] = newDist;
+					q.offer(new Node(next.to, newDist));
+				}
+			}
+		}
+	}
+
+}
+```