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public class Main{
    static class ListNode{
        public ListNode(){}
        public ListNode(int val)
        {
            this.val=val;
        }
        int val;
        ListNode next;
    }

    public static void main(String[]args)
    {
        ListNode root01=new ListNode(2);
        ListNode l12=new ListNode(4);
        ListNode l13=new ListNode(3);
        root01.next=l12;
        l12.next=l13;
        ListNode root02=new ListNode(5);
        ListNode l22=new ListNode(6);
        ListNode l23=new ListNode(4);
        root02.next=l22;
        l22.next=l23;
        ListNode res=deal(root01,root02);
        while (res!=null)
        {
            System.out.print(res.val+"_");
            res=res.next;
        }
    }
    static ListNode deal(ListNode l1,ListNode l2)
    {
        int tmp=0;
        int jin;
        ListNode res=new ListNode();
        ListNode head=res;
        while (l1!=null || l2!=null)
        {
            if (l1!=null)
            {
                tmp+=l1.val;
                l1=l1.next;
            }
            if (l2!=null)
            {
                tmp+=l2.val;
                l2=l2.next;
            }
            head.next=new ListNode();
            head=head.next;
            head.val=tmp%10;
            jin=tmp/10;
            tmp=jin;
        }
        if (tmp!=0)
        {
            head.next=new ListNode();
            head.next.val=tmp;
        }
        return  res.next;
    }
}

• 简介
• 做题：是个格式化输出，给一个字符串按下格式

public class Main {
    public static void main(String[]args)
    {
        String s="This utility is a filter which displays the specified files,&nbs***bsp;the standard input, if no files are specified, in a user spec";
        deal(s,16);
    }

    static void deal(String str,int lineNum)
    {
        StringBuilder stringBuilder=new StringBuilder();
        StringBuilder stringBuilder1=new StringBuilder();
        //init
        int count=0;
        int lineCount=0;
        stringBuilder.append("00000000")
                .append(" ");
        int lineLen=0;
        for (char ch:str.toCharArray())
        {
            count++;
            stringBuilder.append(getNum(ch))
                    .append(" ");
            stringBuilder1.append(ch);
            if (count==lineNum)
            {
                lineLen=stringBuilder.length();
                System.out.print(stringBuilder.toString());
                System.out.println(stringBuilder1.toString());
                stringBuilder.delete(0,stringBuilder.length()+1);
                stringBuilder1.delete(0,stringBuilder1.length()+1);
                count=0;
                lineCount++;
                stringBuilder
                        .append(format(getNum(lineCount*lineNum)))
                        .append(" ");
            }
        }
        System.out.print(stringBuilder.toString());
        int tmp=stringBuilder.length();
        while (tmp++<lineLen)
        {
            System.out.print(" ");
        }
        System.out.println(stringBuilder1.toString());
        stringBuilder.delete(0,stringBuilder.length()+1);
        stringBuilder1.delete(0,stringBuilder1.length()+1);
    }

    static String format(String num)
    {
        String res=num;
        while (res.length()!=8)
        {
            res='0'+res;
        }
        return  res;
    }
    static String getNum(int ch)
    {
        int chInt=ch;
        int res=0;
        while (chInt/16!=0)
        {
            res=res*10+(chInt/16);
            chInt-=((chInt/16)*16);
        }
        return res +getChar(chInt);
    }

    static String getChar(int num)
    {
        if(num<10)
        {
            return String.valueOf(num);
        }
        char ch;
        switch (num)
        {
            case 10:
                ch='a';
                break;
            case 11:
                ch='b';
                break;
            case 12:
                ch='c';
                break;
            case 13:
                ch='d';
                break;
            case 14:
                ch='e';
                break;
            default:
                ch='f';
        }
        return String.valueOf(ch);
    }
}

1. 知道Java里的 Timer 么？如果公司现在有个需求，需要自己实现一个 Timer，你会怎么设计？场景：海量任务。
2. 任务怎么存储？怎么查询？系统如何高效的定时？
3. 说说项目，遇到啥问题？有啥难点？特色？

五面（面委会）