Small knowledge, big challenge! This article is participating in the creation activity of “Essential Tips for Programmers”.

This article has participated in the “Digitalstar Project” and won a creative gift package to challenge the creative incentive money.

Unconsciously, it has been updated to 0x40, rearranged the order of the operating system and computer network, and updated the cover of the article. The basic format is still the same, I hope you like it.

408 contains four subjects, including a variety of basic computer theory, even if you do not take the postgraduate entrance examination, it is good to know some basic knowledge. Welcome to me and my column 🔥

Borrow a big man’s words: for a programmer, the basic knowledge of the computer is internal power, is our professional accomplishment, only deep internal power can walk the river’s lake less.

Programmers can go far, can write high-quality code, can quickly find the bottleneck of the system, can quickly find the core functions of the system, and our professional literacy must be related. Only if you know the basics well enough, can you be truly proficient in your work and solve problems more efficiently and gracefully

🚀 Data structure

After performing push(s,5), push(S,2), push(S,4), pop(s,x), getTop(s,x) for an initially empty stack S, the value of x should be ___.

A. 5
B. 2
C. 4
D. 0
Copy the code

parsing

Answer: B

🎵 is stored in last-in, first-out order, so the top element of the stack is 2 after the last 4pop, so choose B.

📺 Operating system

When designing a real-time operating system, the first consideration should be ___.

A. Reliability and flexibility B. Real time and reliability C. Distributive and reliability D. Flexibility and real timeCopy the code

parsing

Answer: B

🎵 Common sense: The concept of real-time is that external events must be processed within a specified time, which ensures the reliability of the system. Real-time operating systems are commonly used in demanding or special applications, such as military equipment systems.

As the name implies, the real-time system must be real-time, but also to ensure reliable, by guessing can also guess ~

🚁 Computer network

A channel with a rate of 300Baud in the 4-bit system will have a rate of ___ (chongqing university 2005)

A. 300bit/s b. 600bit/s c. 1200bit/s d. 2400bit/sCopy the code

parsing

Answer: B

🎵 Baud is the number of symbols transmitted by the digital communication system per unit time (actually, the number of pulse changes). Therefore, 1 Baud means that one symbol is transmitted per second. If a symbol can carry N bits of information, the information transmission rate corresponding to the M Baud rate is Mn(bit/s).

In the 4-bit system, a code element carries 2 bits of information, then:


300 x 2 b i t / s = 600 b i t / s 300 x 2 bit/s = 600 bit/s

🛸 Computer composition principle

Among the four codes of numbers, the one with the largest code value equals the largest truth value is ___ (Xidian University, 2007)

A. The original code B. Radix-minus-one complement C. Complement D. frameshiftCopy the code

parsing

Answer: D

🎵 is used to shift the true value with a bias value, so the larger the code value is, the larger the true value is, and the original size order of the data is maintained. Therefore, the shift is suitable for representing the order of floating point numbers (it is easy to realize the comparison of order size in order operation), so choose D.

The exercises come from @Wangdao Weibo

The analysis is written by myself, if there are any questions or mistakes, please comment.

I am Mancuoj, welcome to pay attention to me and my computer entrance examination column (≧∇ Blue)