closeness centrality 算法java代码

下面是 closeness centrality 算法的 Java 代码示例：

import java.util.*;

public class ClosenessCentrality {

    public static void main(String[] args) {
        int[][] graph = {
            {0, 1, 1, 0, 0},
            {1, 0, 1, 1, 0},
            {1, 1, 0, 1, 1},
            {0, 1, 1, 0, 1},
            {0, 0, 1, 1, 0}
        };
        int n = graph.length;
        double[] closeness = new double[n];
        for (int i = 0; i < n; i++) {
            closeness[i] = getClosenessCentrality(i, graph);
        }
        System.out.println("Closeness centrality:");
        for (int i = 0; i < n; i++) {
            System.out.printf("%d: %.4f\n", i, closeness[i]);
        }
    }

    private static double getClosenessCentrality(int node, int[][] graph) {
        int n = graph.length;
        int[] dist = new int[n];
        Arrays.fill(dist, Integer.MAX_VALUE);
        dist[node] = 0;
        Queue<Integer> queue = new LinkedList<>();
        queue.offer(node);
        while (!queue.isEmpty()) {
            int curr = queue.poll();
            for (int i = 0; i < n; i++) {
                if (graph[curr][i] == 1 && dist[i] == Integer.MAX_VALUE) {
                    dist[i] = dist[curr] + 1;
                    queue.offer(i);
                }
            }
        }
        int sum = 0;
        for (int i = 0; i < n; i++) {
            sum += dist[i];
        }
        return 1.0 / sum;
    }

}

其中，`graph` 表示图的邻接矩阵，`n` 表示顶点数，`closeness` 存储每个顶点的 closeness centrality 值，`getClosenessCentrality` 方法计算某个顶点的 closeness centrality 值。