对数组进行扩容(note)

对数组a[] = {1,2,3,4}进行扩容;
在扩容一个数值成功后询问是否继续进行扩容;
回答为Y则继续可以输入数值;回答为N则退出程序.

import java.util.Scanner;
public class array {
    public static void main(String[] args) {
        //对数组 int[] a = {1,2,3,4}进行扩容
        Scanner input= new Scanner(System.in);
        char answer;
        int[] a = {1,2,3,4};
        do {
        int[] b = new int[a.length + 1];
            for (int i = 0; i < a.length; i++) {
                b[i] = a[i];
            }
            System.out.println("请输入要添加的数字:");
            int num = input.nextInt();
            b[b.length - 1] = num;
            a = b;
            System.out.println("添加后的数组为:");
            for (int i = 0; i < a.length; i++){
                System.out.print(a[i]);
            }
            System.out.println();
            System.out.println("添加成功!是否继续添加?Y/N");
            answer = input.next().charAt(0);
        } while (answer =='Y');
        //输出添加成功,并询问是否继续添加
    }
}