PAT乙级 1005 继续(3n+1)猜想 (25 分) Java 实现

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int n = scanner.nextInt();
        List num_a = new ArrayList();
        ArrayList arrayList = new ArrayList();
        for (int i = 0; i < n; i++) {
            int num = scanner.nextInt();
            num_a.add(num);
            while (num != 1) {
                if (num % 2 == 0) {
                    num = num / 2;
                    arrayList.add(num);
                } else {
                    num = (3 * num + 1) / 2;
                    arrayList.add(num);
                }
            }
        }
        for (int i =0; i