​

​​

Because love so insist, because love so wait. Through the long days without drama to play, finally for the spring of life, mutual encouragement!!

Yesterday, I received a call from Bytedance HR saying that the real estate Development department wanted to make an appointment with me for an interview. I was so surprised that I couldn’t remember when I had submitted my resume. In order to have more time to breathe, I made an appointment with HR in the afternoon of the next day, so I wasted no time in reading the interview

Early this afternoon, I went in the video room waiting for the interview, and then began to sleep (panic can’t calm down, hey hey), when he suddenly heard a little sister talking, so I started sitting up in the dream, I saw a beautiful little sister appears on the screen, my first reaction is HR, so I asked where the interviewer? She said I was the interviewer ah, how did your side echo so noisy, so I’m in a panic to find headphones, and then she said softly, it’s about time, let’s get started, I have to sit down and composure began my self introduction, introduce a formal question and answer session, after the completion of the following is the problem that she asked

Project related

1. Can you describe your project? What was your role and what did you do?

2. What is your understanding of SpringBoot?

3. How did you build your data sheet?

4. Do you have any problems with alipay?

5. What problems did you encounter during the project?

Basic knowledge of

6. What are the basic types of Java?

7. Wrapper class corresponding to the base type

8. What does generics do? Understanding generics? Type wildcard?

9. The equals method

10. The final keyword

11. The static keyword

Continue,break,return

13. What is the difference between static and instance methods?

14. What is concurrency?

15. What should be paid attention to under high concurrency?

16. What concurrency problems have you encountered? How to deal with it?

Program problem

17. Output the result

String a = new String("ab"); 
String b = new String("ab"); 
String aa = "ab"; 
String bb = "ab"; 
if (aa == bb) 
	System.out.println("aa==bb");
if (a == b) 
	System.out.println("a==b");
if (a.equals(b)) 
	System.out.println("aEQb");
Copy the code

18. Handwritten singleton mode

class Single { private Single() { } private static volatile Single SINGLE; public static Single getInstance() { if (SINGLE == null) { synchronized (Single.class) { if (SINGLE == null) { SINGLE = new Single(); } } } return SINGLE; }}Copy the code

19. Manual tear algorithm, valid parentheses

public static boolean isValidStr (String str) { // write code here if (str.length() % 2 == 1 || str == null || str.length() == 0) return false; char[] c = str.toCharArray(); Stack<Character> stack = new Stack<Character>(); for (int i = 0; i < c.length; i++) { if (c[i] == '{') stack.push('}'); else if (c[i] == '[') stack.push(']'); else if (c[i] == '<' ) stack.push('>'); else if (c[i] == '(') stack.push(')'); else { if (c[i] ! = stack.pop()) return false; } } if (stack.isEmpty()) return true; else return false; }Copy the code

20. Create a handwritten SQL statement to query records with the same name

id

name

1

Xiao Ming

2

Xiao Ming

3

Small fang

SELECT id,name FROM `table` WHERE name IN (SELECT name FROM `table` t GROUP BY name HAVING COUNT(name) > 1) ORDER BY name;
Copy the code

Write out of the wrong, I asked little sister how to write, little sister called me to check the Internet, I repeatedly induced, little sister said select *… When I add a nested query, I say, “Select *”, I’m sure I’ll get scolded. She asks, “Why not?” If you select * from a table where there are many columns, select * from a table where there are many other columns that need to be indexed. This will affect performance.

An exciting rhetorical session

21. Main business of the Department

22. Main technology stacks used (mention bytes mainly Golang and Python)

23. What do you think I could have done better about my interview?

(Little sister said my expression ability is good, but it is too careless, woo woo, I said it is the first time to open a video or female interviewer is not suitable, and then the first time to write code whiteboard, little sister said blame me for affecting your play, hey hey hey, REALLY dare not say, I will say it behind my back)

The pleasant interview ended like this. During the whole process, I felt that the questions I asked were very basic, but there were still many small mistakes. I was too careless. Effective bracket is very simple algorithm of a subject, but also for some special cases forgot to consider, for STR = = null | | STR = = length () = = 0, and also forgot to consider, when the odd then SQL statements for too long didn’t write, also forgot how to write, But little sister also line a little bit remind me to constantly improve, very patient and professional, feel or received a lot of things, continue to refueling!!

​​

​