2021.11.1 summary
If you see this sentence, it means that my autumn recruitment is over, I have got the offer from Baidu and Bytedance, and I plan to join bytedance in this school recruitment, I hope to have a good opportunity in the word energy saving.
better
Autumn recruit began
2021.10.20
Bytedance Official Approval (3)
The maximum product word count group hand tear weight problem has five weights, 2g, 3G, 5G, 8g, 16g, there is a weight problem, how to find out, say ideas
When did you learn Android? Is there any android class on campus? What about Https encryption? DNS resolution process? What about deadlock generation and avoidance? How does TCP guarantee security? What about synchronized? Does it guarantee visibility? What properties does volatile guarantee? What is instruction reorder? Know about dynamic proxies? What about plugins? Why do you want to learn about plug-ins and hot fixes? What about generic erasure? What about thread pools? What does a thread pool do? How do I implement a thread pool myself? What are the difficulties in your project? What about event distribution? How do I wrap an onClickListener myself? Read what source code? What is the difference between MVC, MVP and MVVM? Any new skills you’d like to learn? What career plan do you have? What are your strengths and weaknesses? Do your weaknesses affect your work? Do you know how bytes work? What’s the schedule on Mushroom Street? What’s your school schedule like? Is there any requirement for working place? Which offer is available at present?
Question: What are your weaknesses?
Read the source code, the source code understanding is not enough, the foundation will continue to strengthen
2021.10.18
Bytedance Official Approval (2)
There are three threads, write the code to loop to print ABC 10 times, such as ABCABCABCABC… Hand to tear
What do you do at mushroom Street? What are the four citations? Have you ever used a virtual reference? Https encryption say? What is the difference between SSL encryption and HTTP plaintext transmission? What are the public and private keys? Is there a data interception problem after the server requests the public key maliciously? What does the final keyword do? Class, method, variable? When does the Jvm do garbage collection? Do I have to wait for the Jvm to reclaim automatically? Will system.gc () always be garbage collected? Does that mean it doesn’t work? Garbage collection algorithm introduced one you are most familiar with? What is accessibility analysis? Which objects can be used as GC Roots? If you were to do accessibility analysis, would you use BFS or DFS? What about the tag clearing algorithm? What are your two points?
2021.10.14
Bytedance Official Approval (1)
Intersecting linked list by hand
Tell me about your job on Mushroom Street? What business logic has been exposed to? What’s the difference between ListView and RecyclerView? Have you used RecyclerView’s Level 3 custom cache? Hint: How is hint implemented? What about the event distribution mechanism? What are the three methods of event distribution? How is the click event sequence handled? How do I wrap an onClickListener myself? What performance tuning work did you do? How to tell when to use a LinearLayout or a RelativeLayout? Why does nesting affect performance? How to use ViewStub? How to use include tags and merge tags? Why move ViewPager to ViewPager2 in your own project? How to resolve the event conflict inside? Why does event conflict occur? What are the specific reasons? What about Dalvik and ART? What is the difference between compiling ART and Dalvik? . Apk file packaging process? What does AOT do? What about plugins and hot fixes? What memory partitions does the JVM have? What’s in the virtual machine stack? What is the local variable scale? What does dynamic linking do? Where does the virtual machine stack live? What’s in the stack frame? How do memory leaks occur? What are the most common conditions for memory leaks in Android? Why does Handler leak memory? How to solve it?
Which memory partitions in the Jvm does this code use?
Object a = new Object();
static Object b = new Object();
void count(Object cc){
Object d = new Object();
}
Copy the codeQ: Is the byte interview project or foundation? What do I need to strengthen?
Everyone is different. Look at the resume. You can go back and think about the questions you didn’t answer
2021.10.11
Quick Hand (1)
A random array of 0, 1, and 2 numbers requires no extra space, and a single traversal makes the final sort look like 00001112222
Are there any requirements for working location? What difficulties did you encounter during the learning process? How to solve it? What is the most impressive difficulty you have met? What’s the difference between synchronous and asynchronous? Does asynchrony block? What’s the difference between serial and parallel? What is the difference between concurrency on a single-core CPU and concurrency on a multi-core CPU? What are the implications of synchronous concurrency and asynchronous serial? How do I resolve Hash conflicts? Where is the general linked list method used? How do I traverse only once to find the middle node of a one-way list? How to design a queue with priority weights? Best and worst time complexity for fast sorting? How do you derive that? The idea of fast row? Can a benchmark only be based on one side? Can it be random? How do random benchmarks perform fast sorting? Insert sort time complexity? Have you used MySql? What fields are used for modification? Select * from B where Key and Value exist and select * from A where Key and Value exist. What are the characteristics of TCP? Is it reliable transmission? Does TCP lose packets? What are the features of UDP? How is TCP traffic control implemented? What requests do you often make? What’s the difference between a Post request and a Get? How is Https encryption implemented? How is an Http request initiated? Which layer of protocol is Https? How does SSL encryption resolve public keys? What is the DNS resolution process? What DNS is above the root domain DNS?
2021.10.8
OPPO (a)
Which blog sites do you usually visit? When do you study? Not planning to take the postgraduate entrance exam? Did you work on a project your freshman year or sophomore year? What are the better projects to do? Where do you feel you have made the most progress? What are the benefits of working? How to optimize network performance? What do you think could be improved in your project? What are TCP sticky and unpack? Three handshake introductions? What is the significance of the three handshakes? What is the TCP 504 status code? Which data container collections do you often use? What are the differences between these data sets? Why is the HashMap load factor 0.75? What is a Hash conflict? How about put, get, and resize? When do you tree and when do you degenerate? Why six and not eight? Do you know innoDb? What’s the difference between Kotlin and Java? What do you do at work? What performance optimization work was done? Know which garbage collectors? What is the G1 garbage collection method? When is the old age recycled?
Q: Where are you from? He doesn’t speak with a mainland accent
It’s Cantonese. Mandarin is not very good
2021.9.26
Ants (2-3)
Did you participate in ACM during university? What did you do freshman and sophomore year? Tell me briefly about your work during your internship. What problem was solved? Tell me something about the Handler? Drawing a View? Why can’t I update the UI on a child thread? How is the tag flow layout implemented? How is the search box round seeding realized? What logic does Flutter do? What are the basic means of performance optimization? Did you know about the internal framework of the old team? Read what source code? Pick one? Http and Https protocol content? What is the specific process of key exchange? Which computer network is software engineering?
Is it possible to go to Beijing?
Self summary
Don’t face Ali… Will become unfortunate. Ali’s process was slow because the written test was done late, and the interviewers felt that they had brushed kpi.
2021.9.24
Baidu (123)
Hand rip singleton mode DCL double check mode Static inner class singleton? Hand to tear
What are the four components and their functions? The Activity lifecycle? Activity A life cycle callback by pressing the Home button? Life cycle call when it flips, right? View event distribution mechanism? How to draw a View? How does the Activity start? What can be used for data storage? SharedPreference? Was it used in the project? Is the first line of code page 2 or page 3? What suffix does Android pack? What is included in APK? Have you tried dragging the.APK package into the AS to see the composition? Know about OOM? What can cause an OOM? What is ANR? How? What’s the difference between API and Implementation in Gradle? Componentized understanding? Unit tests? How to look at the drawing hierarchy of a View? What do you know about performance tuning? Have you tested the drawing time? Understand plugins? Four citations? Class loading mechanism? What are the three types of JVM loaders? Their relationship? Three loaders for Android? What are the ways to create a thread? What do you tend to use? Why is that? Five states of a thread? What kind of lock? What’s the difference between ArrayList and LinkedList? Is ArrayList thread safe? So which collection is thread-safe? What class is a queue? What about a two-ended queue? CAS mechanism? What lock is CAS? What are the principles of object-oriented design? What do design patterns know? What is the five-layer model of computer network? Protocols at each level? Http port number? Process and thread relationship? What can Android cross-process use? What did you learn? How to overcome the difficulties? Have you used Git? Git code submission process? What command is used to append changes? Has resolution adaptation been done?
Do you have any offer now? Why don’t you want to stay with your old club?
Sequential traversal of binary trees? Cross – sequence traversal of binary tree? Hand to tear
What do you do on Mushroom Street? What are the methods of cross-process communication between Linux and Android? What does the Binder mechanism do? Do Binder memory maps have size limits? Drawing a View? What are the three modes of Measure? What do they mean? What are the reuestLayout and Invalid methods for? SparseArray? What about HashMap? Do you know about red black trees? The difference between an interface and an abstract class? Can methods in interfaces not be implemented? Dependency inversion use? What does static modify? CAS mechanism? Is CAS a pessimistic or optimistic lock? What does synchronize mean?
Question link: Baidu female interviewer a lot of? How about my foundation?
(I asked this because my first and second interviews were with female programmers.)
Baidu also has many female programmers. The foundation is quite broad, but I hope I can continue to learn, because some deep things seem to go down
Reverse the m to N list? Hand to tear
The Activity lifecycle? How about starting an Activity?
Personal plans for the future? What are your strengths and weaknesses? Why not stay at the old club? Can you come to Beijing? Are you interested in Baidu? Read what source code? Do you want to enter graduate school? What do you think of Baidu? Why baidu?
Q: How is my foundation?
B: Not bad, but some details need to be learned
2021.9.8
Bilibili (one two)
What if a person could jump any n steps?
Why do you want to learn Android? OkHttp source code: How is the thread pool designed? Some important parameters? The difference between an interface and an abstract class? What is the difference between use and definition? Can interfaces be declared private? Protected? What’s the difference between the four permission modifiers? Can static methods be overridden? Why not? Is there a difference between a += b and a + b? What’s wrong with int + double? Can you compile it? If Integer a = 10, b = 10, a == b, what will be returned? What does “==” compare? Have you seen the source code for HashMap? What’s the difference? What changes have been made to the capacity expansion mechanism? When does it tree? When does a tree degenerate into a linked list? How many loopers can a thread have? A few Handler? What’s the problem with having multiple Loopers? Why doesn’t the main thread need to create a Looper? What’s the difference between Runnable and Message? What is the priority of handleMessage? What life cycle is invoked for A switch from Activity A to B? What lifecycle does the Activity invoke when answering a call?
How do you study? What books have you read? How to solve the problem? What do you think of Android?
What do you do in Mogu Street? What are the specific scenarios? What difficulties have you encountered? Have you looked at the specific numbers of performance optimizations? What are the performance optimizations available? What does a bar chart mean? How does Flutter render work? How does Flutter communicate with Android? What are the differences between Kotlin and Java? What higher-order functions have you used? What is the difference between apply and let? Have you studied the principle of higher order functions? Have you used extension functions? What do we know about coroutines? RecyclerView? Show the principle? The source code? Is the event distribution mechanism understood? How is a View bound to a touch event? Read what source code? The core philosophy of Retrofit? What do hotfix frameworks know? How does thermal repair work? Principle of componentization? Enter url to render specific process? Computer network five layer model? What are the protocols? What are the encryption algorithms?
How to use two stacks and one variable to achieve in-stack inversion of LRU by hand
Q: What does the game department do?
Do in-game SDK development
2021.9.7
Bytedance (1)
Minimum continuous subarray of symmetric binary tree
What profound problems have you encountered? How did you solve the problem? A complete IP address request process? How does DNS resolve IP addresses? How does TCP work? Three handshakes Is it ok to shake hands only twice? What’s the problem? What’s the difference between HTTP and HTTPS? SSL encryption mode? Data structure difference between heap and stack? What’s the difference between a process and a thread? How do processes communicate? What’s the difference between parallelism and concurrency? Does suspending a thread in a process affect the entire process? Deadlock creation? How to avoid it? What about the garbage collection mechanism? What is the difference between a weak reference and a soft reference? How do memory leaks happen? When did you write the project? What knowledge is used? How to design the architecture? What are the object-oriented design principles? What exactly does the Dimicott principle say? How is a single responsibility used? What are the differences and connections between process orientation and object orientation? Three features of object orientation? How to understand polymorphism? The link between polymorphism and Leighian substitution? The purpose of Richter substitution?
Self summary
Byte’s interview was the worst of them all. Foundation is not solid, the eight-part essay back less, can not catch the divergent questions of the interviewer, ah
2021.9.6
Ant Financial (1)
Ps: After a long time, I finished my internship in Mogujie and started autumn recruitment, so this article will continue to be updated
Tell me about your job on Mushroom Street? What features have you written? Home page search box round seeding concrete implementation? How is the waterfall stream label layout implemented? What if each item has different heights? What bugs have been fixed? How to understand the two parameters of onMeasure method? What are the measurement modes? How are these measurement modes different from wrAP_content or match_parent? How to optimize the layout? What methods have been used? Performance comparisons for common layouts? How does Flutter feel to write? How are common components reused? How are request paging parameters optimized for handling? What about componentization? What about the AndroidManifest file? Have you read anything about componentization?
Q: Do ants focus on project experience? How to identify the foundation of a candidate?
It can be seen from the question just now that ant is more focused on project experience. Since we have interviewed many people, we can see whether they have reflected on and improved their needs from the project experience, and how is your foundation
Self summary
The interviewer is very kind, chat like the interview, the experience is very good, but I guess the answer is not very good, because he urged me to do the written test, the score is higher…
Tencent (1)
Unordered array find the median unordered array find the KTH largest rip quick row
What did you find difficult in your study? What’s the progress? MVP structure explain? The MVVM? What are the different reference types in Java? RecyclerView details when using pit and solution? What about event distribution? Do you use a lot of handlers? How does that work? Will Message have concurrency problems when joining the team? Why synchronized instead of mutex? JVM implementations of the synchronized keyword? How many impressions are there of the operating system? What’s the difference between a process and a thread? How is interprocess isolation done? How does thermal repair work? What did you do in Mogujie? Is the architecture of Flutter understood? Advantages of Flutter over native? AOP mechanism for Flutter? Have you seen design patterns? Is there an app?
Q: What questions do I have?
Basic line, free to further progress, operating system and other general knowledge to review in time, coding to test, to write more algorithms
Here are the spring moves
2021.4.15
Tencent (one two)
Unordered linked lists remove duplicates, parentheses match
Why does loop() not cause a deadlock? Why doesn’t it consume CPU resources?
View drawing process, how to intercept events, SurfaceView used?
JVM class loading process, parental delegation mechanism and its advantages, memory model and garbage collection mechanism?
HTTP and TCP? HTTPS encryption principles and functions of certificates? HTTP2.0 feature? The concept of TCP links? The four-wave, three-handshake anomaly?
How to use UDP to implement TCP? What are the TCP mechanisms? How to display the TCP connection page after the network cable is removed?
The thread pool? Process thread difference? What are the methods of message communication?
ListView and RecyclerView cache mechanism comparison, used which image loading library? What is the most important Glide method? What did you do?
MVVM and MVP and MVC architecture? What design patterns do you know?
Have you written Socket programming? Do you know the Kotlin language? Read what source code?
Advantages and disadvantages of multiple inheritance and single inheritance? What is virtual memory? What is CPU affinity? What are the mechanisms for communication between threads?
What have you learned about Android performance optimization?
Q: What are my current problems?
Net operating system does not have their own initiative to dig a certain point, Android to understand the line, willing to read the source code is a good habit
Quick Hand (1)
Reverse linked list (finger offer), minimum array value that can be rotated (Leetcode-154)
The Activity lifecycle? What methods are executed after jumping to Activity B? How about going back from B?
Event distribution mechanism? How to draw a View? If View B has View A in it, how do click events get distributed? What happened?
TCP three handshakes and four waves, why?
HTTPS encryption process?
JVM garbage collection mechanisms and algorithms? Four citations?
Quicksort features and time complexity?
What does the volatile keyword do?
ViewPager how to implement the rotation map Banner?
A new interview opportunity is even more important
2021.4.18 update
Baidu (123)
Bubble sort and its optimization, inverting multiple strings
Four components? The Activity lifecycle? A start B Transparent topic lifecycle changes? Four boot modes? Specific application scenarios? App life cycle?
How many bytes are the eight basic data types in 64-bit and 32-bit machines? HashMap get(), put(), and expansion mechanism? What is the difference between shallow copy and deep copy? Clone () how to implement shallow copy and deep copy?
Handler mechanism, how to create looper in child thread? What data structure is MessageQueue? Should the main thread be created? Why doesn’t the main thread need to be created itself? Where and when was the main thread Looper created? Event distribution mechanism? Why doesn’t the View have an onInterceptTouchEvent() method?
Ever used Bitmap? Have you ever written a Bitmap loading demo? What’s the difference between String, StringBuilder, StringBuffer?
What’s the difference between an array list? JVM memory partitions? A garbage collection mechanism? What can be used as GC Roots for accessibility analysis? Why not use reference counting? What is stored in the virtual machine stack? Which memory partition does String a = “123” use?
Computer network five layer model? Which layer is TCP? What’s the difference between Http and Https? How to encrypt SSL?
What are your plans after graduation? What do you expect from the internship team? Which other houses did you meet with? How long ago? What are your strengths and weaknesses? Which course do you find the most difficult? Why is that?
Q: How should I study after?
Lay a good foundation, learn computer network and operating system, learn more cutting-edge technology
A new interview opportunity is even more important
2021.4.23 update
Mushroom Street (1)
Why use Glide to load pictures? Imagine the caching mechanism for Glide? NestedScrollView and RecyclerView How to cache ViewPager? How to deal with large amount of data? Why does EventBus subscribe via annotations? Why not broadcast with EventBus? How does JSON parse work? Why GSON parsing? What are the inputs and outputs of GSON? How does animation work?
Exceptions and errors? Wait () and notify() applications? Why is String made final? What’s the difference between StringBuilder and StringBuffer? CopyOnWriteArrayList? Serialization and deserialization?
Q: What’s wrong with the learning style?
Very good, later read and write more
CVTE (a)
Find the least frequent character in the character array
Handler mechanism? What’s it like when you’re not texting? What if MessageQueue still has messages when the application ends? Glide source? What is Glide’s advantage over other image loading libraries? What happens from clicking the icon of an icon to launching? How to draw a View? Custom View implementation? How do I prevent UI overdrawing? Which method is involved in UI overdrawing? Can child threads manipulate the UI? ThreadLocal principles? How to implement the Local property? How does OOM work?
What design patterns do you know? How do YOU break singleton? How do I prevent singleton memory leaks? What are the advantages of Hashmap over other containers? How does it work? JVM memory partitions? How do these partitions work? How much heap memory does a phone have?
Http and Https? Why asymmetric encryption? What are certificates for?
Self summary
This CVTE was the most difficult interview among the above interviews. I asked some questions that I had not been in contact with in previous interviews and during study, and it was still difficult for me to ask some questions in depth. It’s still a long way to go. Keep trying
A new interview opportunity is even more important
2021.4.26 update
Mushroom Street 2
The sum of two numbers, what if the given array is ordered?
What are the difficulties of the project? How are the difficulties solved? What impressed you most? Have you seen OkHttp’s onResponse() log yourself? How to locate these problems? What did he probably do? Have you read the source code and core of third-party libraries? Glide?
Know anything about event distribution? What does onInterceptTouchEvent() do? The difference between returning false and true? What courses did you take?
What’s the difference between Http and Https? What is the content of SSL encryption protocol? What is the most important part? Is there only asymmetric encryption in SSL
Which data structures are commonly used? What are the main differences between HashMap 1.7 and 1.8? What is the search complexity of the tree structure? The list? A HashMap?
How many ways are there to communicate between processes?
Q: What’s wrong with the learning style? What do you do during your internship?
Learning way is very good, pay attention to brush algorithm to go back to summary, knowledge mastered but practice with less, when someone took the internship, work and formal staff
A new interview opportunity is even more important
2021.4.27 update
Douyu Live Broadcast (1)
Did you do the project yourself? What difficult problems have you encountered? How to implement the wheel – cast graph?
What’s the difference between “==” and “equals”? Are two objects with the same hashcode equal to equals? What are the basic data types? The difference between an interface and an abstract class? How does Hashmap work? Which design patterns have been used? What are the ways to write a singleton pattern? How to choose the corresponding writing method?
Handler mechanism? The difference between sendMessage and sendDelayMessage? The arrangement of delayed messages? How many handlers can there be? How many loopers can there be? How many MessageQueue can there be? Event distribution mechanism? What’s the difference in event distribution between a View and a ViewGroup? What are the Android layouts? Layout performance? How does the layout draw the XML onto the interface? Custom View drawing process? How to prevent multiple clicks? How does Glide source code prevent memory leaks? What is available in OOM? Four citations? How to solve a singleton memory leak using an Activity? What if you have to associate an Activity? Have you met OOM? What’s the difference between Fragment and View?
Question: What foundation do I lack? What is your future study direction?
Basic is also ok, the source code can also understand, some libraries used by the project is relatively backward, to timely learn more new functions and third-party libraries
A new interview opportunity is even more important
2021.4.29 update
Jingdong (one two)
What is the idea of building a project from scratch? What architectures are used? What problems did the project solve? What does EventBus do in your project? What does the animation do? Event distribution mechanism? How many options are there to distribute to the final View? Internal interception and external interception? Which methods need to be overridden? Message mechanism? MessageQueue data structure? How are messages arranged? Root cause of Handler memory leak? How to determine which Message from which Handler is sent from multiple messages sent by multiple handlers? The core logic of OkHttp? What are some useful design patterns? What are the strengths and weaknesses of the Builder model? What interceptors does he have? Read what source code? How to draw a View? What custom views have you made?
What specific app design did the project refer to? How to load image optimization? How to adapt to different phone resolutions?
What GC Roots do you have? JVM markup algorithm?
Do you usually study most of your books? What other way is there? Is it self-taught? What do you want to know about JINGdong? Are you still interested in our project and business? What advantages do you think you have over others? When can I start the internship?
A new interview opportunity is even more important
2021.5.7
Douyu Live Broadcast (2)
What are the difficulties of the project? Read what source code? EventBus design philosophy? Core code flow? What’s the difference between a process and a thread? Have you ever used multithreading? What’s the difference between asynchronous and synchronous? What’s the difference between HashMap and ConcurrentHashMap? The Activity lifecycle? What’s the difference between an Activity and a Fragment?
Select * from male (age > 20); select * from male (age > 20);
Question: Is the understanding of some concepts correct? Do you need to review the database?
The basic understanding is correct, but it is based on books, and you will understand more in practice. Database mobile terminal use less, but the basic will