程序不会打印出交叉点或差异！ 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;
    }
}

The requirements are that I must use methods and loops to reach the solution. Also the intersection and difference methods MUST return an int as part of the assignment instructions!

Test Input:

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

I think i found your errors:

1. You use set.length (or setA.length or ...) instead of the method parameter ( size or sizeA or ...) multiple times.

   Especially in your sort method this is problematic: the sorted arrays will start with 0 s. You don't recognize this, since you ignore 0 s in your print method. Print it the way you print the intersection and difference and you'll see the error.

2. You pass intersect as parameter to your difference method instead of difference .

3. You create a new array in your intersection method. This replaces only the local array, not the one created in your main method. ( int arrays are initialized with 0 s)