Java匹配数组

Question

接受两个整数数组的方法。该方法返回一个整数数组，其中包含数组 int[]a 中的所有元素，这些元素也按照它们在 int[]a 中的原始顺序出现在数组 int[]b 中。

这是它应该输出的内容:

input: {1, 2, 3, 4, 5, 6, 7, 3, 8, 9, 2, 10}, {3, 2, 7, 12, 3, 9, 5, 2}

output: {2, 3, 5, 7, 3, 9, 2}



input: {4, 7, 1, 6, 9, 2, 3, 1}, {8, 5, 2, 1, 9, 4}

output: {4, 1, 9, 2, 1}

我尝试过这样的事情只是为了测试它以了解它，但我还是做不到。

    public static void arraysMatching(int[] s1, int[] s2) {
    ArrayList<Integer> storage = new ArrayList<Integer>();
        for (int i = 0; i <= s1.length; i++) {
            for (int j = 0; j <= s2.length; j++) {
                if (s2[j] == s1[i]) {
                    storage.add(s2[j]);
                    break;
                }
            }
            break;
        }
        System.out.println(storage);

    }

测试用例:

int [] m1 = {1, 2, 3, 4, 5, 6, 7, 3, 8, 9, 2, 10};
int [] m2 = {3, 2, 7, 12, 3, 9, 5, 2};
System.out.println(Arrays.toString(arraysMatching(m1, m2)));
Should print out [2, 3, 5, 7, 3, 9, 2]

Answer 1

添加到 Codors answer , 让方法返回 int[]:

public static int[] arraysMatching(int[] s1, int[] s2) {

    ArrayList<Integer> storage = new ArrayList<>();
    //for (int i = 0; i <= s1.length; i++) {
    //wrong. change <= to  < or better:
    for (int i : s1) {

        //for (int j = 0; j <= s2.length; j++) {
        //wrong. change <= to  < or better:
        for (int j : s2) {
            if (j == i) {
                storage.add(j);
                break;
            }
        }
    }

    //if you can use streams do
    //return  storage.stream().mapToInt(i->(int)i).toArray();

    //alternatively
    int[] returnArray = new int[storage.size()];
    for(int i=0; i< storage.size(); i++) {
        returnArray[i]=storage.get(i);
    }
    return returnArray;
}

因此您可以将它与 System.out.println(Arrays.toString(arraysMatching(m1, m2))); 一起使用