java - 查找两个数组的并集

Question

我正在尝试查找由用户输入创建的两个数组的并集。我不断得到:

线程“main”中的异常 java.lang.ArrayIndexOutOfBoundsException: 4 在 TwoSets.main(TwoSets.java:47)

import java.util.Scanner;

public class TwoSets 
{

public static void main(String[] args) 
{

    int i, array, choice;
    Scanner input = new Scanner(System.in);

    System.out.print("How many numbers do you want in each set? ");
    array = input.nextInt();

    int set1[] = new int[array];
    int set2[] = new int[array];
    int set3[] = new int[array*2];

    for(i=0;i<set1.length;i++)
    {
        System.out.print("Enter a number from the first set: ");
        set1[i] = input.nextInt();
    }

    System.out.print("\n");

    for(i=0;i<set2.length;i++)
    {
        System.out.print("Enter a number from the second set: ");
        set2[i] = input.nextInt();
    } 

    System.out.print("Enter 1 to find Union\n" + "Enter 2 to find Intersection\n" + "Enter 3 to find Difference\n");
    choice = input.nextInt();

上面的代码正在初始化并获取用户输入，工作正常。下面的代码不起作用。

    if(choice == 1)
    {
        for(i=0;i<array;i++)
        {
            set3[i] = set1[i];
        }

        for(i=array;i<array*2;i++)
        {
            boolean check = Union(set2[i], set3);
            if(check == false)
            {
                set3[i] = set2[i];
            }
        }
        for(i=0;i<set3.length;i++)
        {
            System.out.print(set3[i]);
        }
    }
}

public static boolean Union(int number, int[] array)
{
    for (int i : array )
    {
        if (i == number)
        {
            return true;
        }
    }
    return false;
}
}

Answer 1

set2 具有数组长度，但在:

for(i=array;i<array*2;i++)
        {
            boolean check = Union(set2[i], set3);
            if(check == false)
            {
                set3[i] = set2[i];
            }
        }

您在循环中使用 array*2 。我认为这是一个错误。