返回包含集合的两个数组之间共享的元素数。返回两个列索引数组共享的元素数。

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//package com.nowjava;//时代Java公众号 - nowjava.com 提 供


public class Main {

    public static void main(String[] argv) throws Exception {

        int[] arra = new int[] { 34, 35, 36, 37, 37, 37, 67, 68, 69 };

        int[] arrb = new int[] { 34, 35, 36, 37, 37, 37, 67, 68, 69 };

        System.out.println(countCommonElements(arra, arrb));

    }


    /**

     * Returns the number of elements shared between the two arrays containing

     * sets.<p>

     *

     * Return the number of elements shared by two column index arrays.

     * This method assumes that each of these arrays contains a set (each

     * element index is listed only once in each index array). Otherwise the

     * returned number will NOT represent the number of unique column indexes

     * shared by both index array.

     *

     * @param arra int[]; first array of column indexes.

     *

     * @param arrb int[]; second array of column indexes

     *

     * @return int; number of elements shared by <code>a</code> and <code>b</code>

     */

    public static int countCommonElements(