I switched to non-disciplinary classes and took more than a dozen offers in two months, including major Internet companies, central enterprises, state-owned enterprises, banks, etc. Let’s see what I met (some memories). In short, when interviewing state-owned enterprises and other enterprises, there will be some interesting questions and group scenes will also appear.
1 Ali side
The difference between pointer and reference
define和const
Inline functions and define
c++ memory management
The difference between stack and heap, global variables and local variables
c++ polymorphism, virtual function, pure virtual function
The benefits of polymorphism
Database index, for a sentence to ask whether there is an index used, how to achieve the bottom layer
B tree and B+ tree
Hash collision
Talk about common sorting algorithms and time and space complexity
TCP, UDP, reliable transmission, when is the network congested
Why memory alignment
Asymmetric encryption and symmetric encryption
2 Telecommunications Research Institute
Will the operating system linux be used and what system to use
static variables and local variables know not
Memory overflow
What operation will the server fail
Does c++ use a lot?
What position do you want to do
Will the linux command
epoll and select
sed and grep do not know
awk
Any hobbies
Can you play bridge?
Did you play billiards well?
Basketball
What rank is the king of glory?
Where do you like to play
Which laboratory is the instructor called
Come to your college in two days, remember to come
This one. . . .
3 Pinduoduo
Can you debug with gdb? Talk about the principle of gdb debugging
Have you used git, talk about the principle
Which linux commands are you familiar with, answer to learn about copying, and then ask, tell me about the principle of cpu
The difference between https1.1 and 2.0 is answered, why and how is it realized?
What are the features of c++11, you can implement shared_ptr
Why is tcp reliable? How to set the time of tcp retransmission? (A message can not get ACK)
How to schedule multiple threads
Have you used mysql, talk about B+ tree
This is your written test. Let’s take a look at your algorithm. You did the third question wrong. Do you have any ideas? If you don’t, think about it now.
memcpy write
write strcpy
Do you understand polymorphism in C++, then you can implement it in C.
The operating system forgot.
4 Tencent TEG
Good language (C language, C++), understanding of C++
Do you have much experience with Linux project platforms?
The difference between malloc and new allocated memory
Implementation principle inside malloc
The maximum memory space (32 bits) that malloc can allocate (the segment is mentioned). If 2G of memory is applied for, will it immediately correspond to the physical address? If not, will there be a page fault interrupt when writing data to it?
How to check the range and size of segments
The part of the elf target executable file, what is the difference between the segment in the elf file and the segment at runtime
How to load object files into memory
Handling process of page fault interrupt
It is mentioned that page fault interruption will occur when page feed is swapped out. Is it necessarily caused by page feed? What about the unallocated space mentioned above?
Which CPU and registers participate in this page fault interrupt in the system and hardware.
Mentioned MMU, CR3 register
In order to speed up the page table conversion, what kind of hardware and software will be used
Do you understand large page memory? What is its concept, what are its advantages and disadvantages.
Advantages: reduce page tables
Do you know much about the compilation part? How is the function call of C language implemented from the perspective of assembly?
Mentioned ebp, esp function stack, jmp jump
Linux library function memcpy, can you think of a more efficient memory copy method? In addition to byte-by-byte copy, is there any better performance method.
What are the components of the CPU of a process running on Linux, the overall CPU occupancy and the occupancy of each block of the CPU. How to use top to see the components of a process's CPU usage. (Is there less work done on performance optimization?)
There are many performance optimization related classes in C++ STL. Do you know this? How big is the STL string class itself, and how do you store strings? How does vector dynamically expand space?
Mentioned size() and capacity()
Pick one of the deepest technical points studied. Pick what you are best at, such as network programming, system kernel, etc.
The difference between optimistic lock and pessimistic lock
Mentioned CAS
Asked about the application scenarios of CAS. Does CAS allow a short access delay?
How does CAS implement the lock primitives on the Linux system?
Talking about the source code in RING, using multiple structs, but he said that he did not talk about the point. What I want to ask is the underlying principle (either assembly or x86 architecture) (maybe single-sentence assembly language, or bus lock )
The role of the volatile keyword? What is the main problem? In order to prevent the compiler from optimizing?
In order to prevent the compiler from optimizing, the most important thing is what optimization is done, how to understand and read this value directly
What kind of hardware is the cache?
Are registers also part of the cache?
Which one is faster for CPU to access registers, cache, or memory? What is the time period of the visit? How many times faster?
Which of the projects and things done by undergraduates, graduates, and internships is more satisfactory and can reflect your own abilities?
The advantages and disadvantages of good technology and good way of doing things?
Where are you from? Why not participate in the recruitment of interns?
Do you have any question?
5 a line
Do you know precompilation
You said define, then what is the difference between it and function
Which is faster and why
You mentioned stack, then you talk about stack and heap
Have you ever done an internship? What does Huawei do?
How many people in your class have internships
Made a simple algorithm problem
Is there any change?
Overtime?
What direction do you want, c++ or java or python
What does Bishe do
Several people do
Will the database
I did a few questions on the computer test
Where your house
Where do you plan to work
Do you like wuhan
Do you have a girlfriend
Almost that's it
6 Chaiyi Technology
Why not use CNN, use LSTM
Why LSTM can alleviate the disappearance of gradients
What is gradient vanishing and gradient explosion
Why extract timing information
Talk about RNN and CNN
You talk about virtual pointers
Write a singleton pattern
Can other processes access the instance of the singleton pattern created by this process?
You talk about memory leaks
There are several virtual function tables
while(1) dead loop
attention mechanism
Talk about the constructor and destructor in inheritance
Let's talk about the wild pointer
What courses have you studied, then tell me about the red-black tree
Tell me how to insert a node into a balanced binary tree
How to retransmit TCP
Why shared memory can realize process communication
Each process has its own memory, why can access shared memory
Do you know Hill sort, is it faster than direct insertion sort, why, and what is the average time complexity?
Singly linked list
Write a reverse singly linked list
7 Summary
If you try state-owned enterprises, research institutes, banks, etc., you can participate in their training program in advance , so that the chances of entry will be greater. Of course, if you are 985, the chances of entering these companies will indeed be greater. Whoever makes someone is 985, right, we have to pay for our own efforts. But the opportunity must be for the friends who are always ready, so, go ahead!
Finally, I wish everyone a good offer.