[JAVA-자바] 14938번: 서강그라운드

 

소스코드:

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.PriorityQueue;
import java.util.StringTokenizer;

public class Main {
    static BufferedReader br;
    static BufferedWriter bw;

    static int maxItemCount;
    static int NODE_COUNT;
    static int NEAR;
    static int WAY_COUNT;
    static int[] ITEM;
    static List<List<Node>> nodeList;

    public static class Node {
        int to;
        int cost;

        Node(int t, int c) {
            this.to = t;
            this.cost = c;
        }
    }

    public static void main(String[] args) throws IOException {
        br = new BufferedReader(new InputStreamReader(System.in));
        bw = new BufferedWriter(new OutputStreamWriter(System.out));

        StringTokenizer st = new StringTokenizer(br.readLine());
        NODE_COUNT = Integer.parseInt(st.nextToken());
        NEAR = Integer.parseInt(st.nextToken());
        WAY_COUNT = Integer.parseInt(st.nextToken());
        ITEM = new int[NODE_COUNT + 1];
        nodeList = new ArrayList<>();

        for (int i = 0; i <= NODE_COUNT; i++) {
            nodeList.add(new ArrayList<>());
        }

        st = new StringTokenizer(br.readLine());
        for (int i = 1; i <= NODE_COUNT; i++) {
            ITEM[i] = Integer.parseInt(st.nextToken());
        }

        for (int i = 1; i <= WAY_COUNT; i++) {
            st = new StringTokenizer(br.readLine());
            int cur = Integer.parseInt(st.nextToken());
            int to = Integer.parseInt(st.nextToken());
            int cost = Integer.parseInt(st.nextToken());
            nodeList.get(cur).add(new Node(to, cost));
            nodeList.get(to).add(new Node(cur, cost));
        }
        br.close();

        for (int i = 1; i <= NODE_COUNT; i++) {
            maxItemCount = Math.max(maxItemCount, dijkstra(i));
        }

        bw.write(maxItemCount + "\n");
        bw.close();
    }

    public static int dijkstra(int start) {
        PriorityQueue<Node> pq = new PriorityQueue<>((a, b) -> a.cost - b.cost);
        int[] dist = new int[NODE_COUNT + 1];
        Arrays.fill(dist, Integer.MAX_VALUE);
        dist[start] = 0;

        pq.add(new Node(start, 0));

        while (!pq.isEmpty()) {
            Node cur = pq.poll();

            if (dist[cur.to] < cur.cost) {
                continue;
            }

            for (Node next : nodeList.get(cur.to)) {
                int nextNode = next.to;
                int nextCost = cur.cost + next.cost;

                if (dist[nextNode] > nextCost) {
                    dist[nextNode] = nextCost;
                    pq.add(new Node(nextNode, nextCost));
                }
            }
        }

        int total = 0;
        for (int i = 1; i <= NODE_COUNT; i++) {
            if (dist[i] <= NEAR) {
                total += ITEM[i];
            }
        }

        return total;
    }
}

 

글의 내용 중 잘못된 점이나 수정이 필요한 부분, 혹은 궁금한 사항이 있다면 언제든 댓글로 남겨주시면 감사하겠습니다.

여러분의 피드백은 더 나은 글을 작성하는 데 큰 도움이 됩니다. 감사합니다.