题解 | #整型数组合并#

import java.util.*;

// 注意类名必须为 Main, 不要有任何 package xxx 信息
public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);

            int a = in.nextInt();
            int[] arrA = new int[a];
            for (int i = 0; i < a; i++) {
                arrA[i] = in.nextInt();
            }

            int b = in.nextInt();
            int[] arrB = new int[b];
            for (int i = 0; i < b; i++) {
                arrB[i] = in.nextInt();
            }
            Arrays.sort(arrA);
            Arrays.sort(arrB);

            //比较并合并
            int i = 0;
            int j = 0;
            List<Integer> list =  new ArrayList<>();
            while (i < arrA.length && j < arrB.length) {
                if(arrA[i] < arrB[j]) {
                    if (i ==0 || i > 0 && arrA[i - 1] != arrA[i]) {
                       list.add(arrA[i]);
                    }
                    i++;
                }else if (arrA[i] == arrB[j]) {
                    if (i == 0 || i > 0 && arrA[i - 1] != arrA[i]) {
                       list.add(arrA[i]);
                    }
                    i++;
                    j++;
                }else if (arrA[i] > arrB[j]) {
                    if (j == 0 || j > 0 && arrB[j - 1] != arrB[j]) {
                        list.add(arrB[j]);
                    }
                    j++;
                }
            }
            while (i < arrA.length) {
                if (i == 0 || i > 0 && arrA[i - 1] != arrA[i]) {
                    list.add(arrA[i]);
                }
                i++;
            }

            while (j < arrB.length) {
                if (j == 0 || j > 0 && arrB[j - 1] != arrB[j]) {
                    list.add(arrB[j]);
                }
                j++;
            }

            //输出结果
            for(int num : list){
                System.out.print(num);
            }

    }
}