Introduction to basic syntax and data types of C language

C language is a widely used computer programming language that is efficient, flexible and powerful. To be proficient in programming in C language, you first need to understand its basic syntax and data types. This article will introduce the basic syntax and data types of C language and give examples.

1. Basic syntax

1.1 Comments

In C language, comments can be used to explain the code to facilitate understanding and maintenance. Comments can be divided into single-line comments and multi-line comments.

// This is a single line comment

/* This is
Multi-line comments */

1.2 Keywords

There are some keywords in C language that are used to express specific meanings and cannot be used as variable names. Common keywords include int, char, if, else, etc.

1.3 Variable declaration

In C language, variables need to be declared first and then used. When declaring a variable, you need to specify the variable type and variable name.

int num; // Declare an integer variable num

1.4 Function definition

In C language, a function is the execution unit of code, used to encapsulate specific functions . Function definition includes function return type, function name, parameter list and function body.

int add(int a, int b) {
    return a b;
}

1.5 Conditional statements

Conditional statements are used to execute different code blocks based on conditions. Common conditional statements include if statements and if-else statements.

int x = 5;
if (x > 0) {
    printf("x is positive");
} else {
    printf("x is non-positive");
}

1.6 Loop statement

Loop statement is used to repeatedly execute a specific block of code. Common loop statements include for loop, while loop and do-while loop.

for (int i = 0; i < 5; i ) {
    printf("%d ", i);
}

2. Data types

2.1 Basic data types

C language provides some basic data types for storing different types of data. Common basic data types include int, char, float, and double, etc.

int num = 10;
char ch = 'A';
float f = 3.14;
double d = 3.1415926;

2.2 Array

An array is a collection that stores data of the same type. Array elements are accessed through subscripts. The declaration of an array requires specifying the array type and array size.

int arr[5] = {1, 2, 3, 4, 5};

2.3 Pointer

Pointer is a variable that stores the address of a variable and is used for indirect access data in memory. Pointer variables need to specify the pointer type and the variable type pointed to.

int *ptr;
int num = 10;
ptr = #

2.4 Structure

Structure is a custom data type that can store multiple different types of data. The declaration of a structure requires specifying the structure name and member variables.

struct Student {
    char name[20];
    int age;
};
struct Student stu;

Through the above introduction, we understand the basic syntax and data types of C language. To master the C language proficiently, you need to practice more and continue to study in depth. Hope this article helps you!

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