java - 程序不会打印出交集或差集!有什么建议么？

Question

import java.util.Scanner;

public class setPractice {
    public static Scanner kbd;

    public static final int MAXSIZE = 20;

    public static void main(String[] args) {
        kbd = new Scanner(System.in);
        int[] setA = new int[MAXSIZE];
        int[] setB = new int[MAXSIZE];
        int[] intersect = new int[MAXSIZE];
        int[] difference = new int[MAXSIZE];
        int sizeA, sizeB, interSize, diffSize;

        System.out.print("How many numbers will be in the 1st set: ");
        sizeA = kbd.nextInt();
        while (sizeA > MAXSIZE) {
            System.out
                    .print("Error: Set size is too large. Re-enter set size: ");
            sizeA = kbd.nextInt();
        }
        System.out.println("Enter list of integers for 1st set: ");
        getData(setA, sizeA);
        sort(setA, sizeA);
        System.out.println("The ascending order for 1st is:");
        print(setA, sizeA);

        System.out.print("How many numbers will be in the 2nd set: ");
        sizeB = kbd.nextInt();
        while (sizeB > MAXSIZE) {
            System.out
                    .print("Error: Set size is too large. Re-enter set size: ");
            sizeB = kbd.nextInt();
        }
        System.out.println("Enter list of integers for 2nd set: ");
        getData(setB, sizeB);
        sort(setB, sizeB);
        System.out.println("The ascending order for the 2nd set  is:");
        print(setB, sizeB);

        interSize = intersection(setA, setB, sizeA, sizeB, intersect);
        System.out.print("The intersection of the two sets is: ");
        for (int x = 0; x < interSize; x++) {
            System.out.print(intersect[x] + " ");
        }

        diffSize = difference(setA, sizeA, setB, sizeB, intersect);
        System.out.print("\n\nThe difference of A-B is: ");
        for (int x = 0; x < diffSize; x++) {
            System.out.print(difference[x] + " ");
        }
    }

    public static void getData(int[] set, int size) {

        for (int x = 0; x < size; x++) {
            int num = kbd.nextInt();
            int count = search(set, size, num);
            if (count == 0)
                set[x] = num;
            else
                x--;
        }
    }

    public static int search(int[] set, int size, int num) {

        int count = 0;

        for (int x = 0; x < size; x++) {
            if (num == set[x])
                count++;
        }
        return count;
    }

    public static int difference(int[] setA, int sizeA, int[] setB, int sizeB,
            int[] resultSet) {

        int y = 0;
        for (int x = 0; x < sizeA; x++) {
            int num = setA[x];
            int found = search(setB, sizeB, num);
            if (found == 0) {
                resultSet[y] = num;
                y++;
            }
        }
        return y;
    }

    public static void sort(int[] nums, int size) {
        int temp;
        for (int i = 0; i < nums.length - 1; i++) {
            for (int j = 0; j < nums.length - i - 1; j++) {
                if (nums[j] > nums[j + 1]) {
                    temp = nums[j];
                    nums[j] = nums[j + 1];
                    nums[j + 1] = temp;

                }
            }
        }

    }

    public static void print(int[] nums, int size) {
        for (int i = 0; i < nums.length; i++) {
            if (nums[i] != 0) {
                System.out.println(nums[i]);
            }
        }
    }

    public static int intersection(int[] setA, int[] setB, int size, int sizeB,
            int[] resultSet) {
        int count = 0;
        for (int i = 0; i < setA.length; i++) {
            for (int j = 0; j < setB.length; j++) {
                if (setA[i] == setB[j]) {
                    count++;
                    break;
                }
            }
        }
        resultSet = new int[count];
        count = 0;
        for (int i = 0; i < setA.length; i++) {
            for (int j = 0; j < setB.length; j++) {
                if (setA[i] == setB[j]) {
                    resultSet[count++] = setA[i];
                    break;
                }


            }
        }
        return count;
    }
}

要求是我必须使用方法和循环来达到解决方案。此外，交集和差分方法必须返回 int 作为赋值指令的一部分!

测试输入:

How many numbers will be in the 1st set: 3
Enter list of integers for 1st set: 
34
2
56

The ascending order for 1st is:
2
34
56

How many numbers will be in the 2nd set: 4
Enter list of integers for 2nd set: 
56
2
33
6

The ascending order for the 2nd set  is:
2
6
33
56

The intersection of the two sets is: 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 

The difference of A-B is: 

Answer 1

我想我发现了你的错误:

1. 您多次使用set.length(或setA.length或...)而不是方法参数(size或sizeA或...)。

   特别是在您的 sort 方法中，这是有问题的:排序后的数组将以 0 开头。您无法识别这一点，因为您忽略了 print 方法中的 0。按照打印交集和差值的方式打印它，您就会看到错误。

2. 您将 intersect 作为参数传递给 difference 方法，而不是 difference。

3. 您在 intersection 方法中创建一个新数组。这仅替换本地数组，而不替换在 main 方法中创建的数组。 (int 数组用 0 初始化)