给出两个无序整数集合A、B，求出他们的交集、并集以及B在A中的余集，输出从小到大。用Java实现

可以使用Java的集合类来实现交集、并集和差集的计算。以下是示例代码：

import java.util.*;

public class SetOperations {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        Set<Integer> setA = new HashSet<>();
        Set<Integer> setB = new HashSet<>();
        
        System.out.print("Enter elements of set A separated by space: ");
        String[] inputA = sc.nextLine().split(" ");
        for (String s : inputA) {
            setA.add(Integer.parseInt(s));
        }
        
        System.out.print("Enter elements of set B separated by space: ");
        String[] inputB = sc.nextLine().split(" ");
        for (String s : inputB) {
            setB.add(Integer.parseInt(s));
        }
        
        // Intersection
        Set<Integer> intersection = new HashSet<>(setA);
        intersection.retainAll(setB);
        System.out.println("Intersection: " + intersection);
        
        // Union
        Set<Integer> union = new HashSet<>(setA);
        union.addAll(setB);
        System.out.println("Union: " + union);
        
        // Difference
        Set<Integer> difference = new HashSet<>(setB);
        difference.removeAll(setA);
        System.out.println("B complement A: " + difference);
    }
}

示例输入输出：

Enter elements of set A separated by space: 1 2 3 4
Enter elements of set B separated by space: 3 4 5 6
Intersection: [3, 4]
Union: [1, 2, 3, 4, 5, 6]
B complement A: [5, 6]