In the C language, macro definitions are a very powerful tool that can help us simplify code, improve readability, and maintainability. This article will detail macro definitions in C, including their basic concepts, usage methods, and some common application scenarios. What is a Macro Definition? A macro definition is a preprocessor directive used for text … Read more
In C language, input and output are important ways for programs to interact with users.<span>scanf</span> and <span>printf</span> are the two most commonly used functions in C for handling input and output. This article will provide a detailed introduction to the usage of these two functions, along with code examples to help everyone understand. 1. printf … Read more
Click the blue text above: IoT Guesthouse to follow us In embedded C language interviews, in addition to basic syntax and data structures, some advanced features such as macro definitions, storage classes, and type modifiers will also be emphasized. These knowledge points not only test your mastery of syntax but also your understanding of the … Read more
Introduction: New students entering computer science often feel confused by the abundance of `#include <stdio.h>`: “It’s 2025, and the school is still teaching the ancient C language? Isn’t Java or Python better?” Today, we will dissect this classic debate—what languages should computer science students actually learn? I. C Language: The “Atomic Structure” of the Computer … Read more
Embedded Linux: A Comprehensive Guide to Pointers This article aims to summarize the learning of pointers in C language. If you like it, feel free to follow, as I will continue to update knowledge related to Embedded Linux. 1. The Relationship Between Pointers and Arrays 1. What is a Pointer? Like data types such as … Read more
1. Set a specific bit to 1: Macro #define setbit(x,y) x|=(1<<y) – Sets the y-th bit to 1.2. Set a specific bit to 0: Macro #define clrbit(x,y) x&=~(1<<y) – Sets the y-th bit to 0.3. Toggle a specific bit: Macro #define reversebit(x,y) x^=(1<<y) – Toggles the y-th bit. Note: XOR results in 0 for the … Read more
01 Given that x, y, and t are all int type variables, after executing the statement: x=y=3; t=++x||++y; the value of y is ( ) A) Undefined value B) 4 C) 3 D) 2 Answer: C Explanation: The short-circuit characteristic of || (logical OR): If the expression on the left of || is true (non-zero), … Read more
The application of modulus (<span><span>%</span></span>) and integer division (<span><span>/</span></span>) in C language. Code section: #include <stdio.h> #include <math.h> /*(Sum of Digits) Write a function that takes an integer and returns the sum of its digits. For example, given the number 7631, the function should return 17 (Explanation: 7 + 6 + 3 + 1 = … Read more
Optimizing microcontroller programs usually refers to optimizing program code or execution speed. Optimizing code and optimizing speed are actually a unified contradiction. Generally, optimizing the size of the code will lead to an increase in execution time; if the execution speed of the program is optimized, it usually results in an increase in code size. … Read more
