The basic knowledge of C language must be memorized
Apr 04, 2025 am 08:00 AMThe basics of C language cover data types (integrals, floating point numbers, characters, booleans), variable declarations, operators, process controls, functions, arrays, strings, pointers, and structures. These concepts provide the basis for C language programming, including: integer type: int, short, long floating point type: float, double variable declaration: data_type variable_name; if statement: conditional judgment and code execution for loop: repeat code function definition by specific times: return_type function_name(parameter_list); array declaration: data_type array_name[si
C language basic knowledge must be memorized
1. Data type
- Integer types: int, short, long
- Float number type: float, double
- Character type: char
- Boolean type: bool
2. Variables
- Declare variable: data_type variable_name;
- Variable name rules: start with a letter or an underscore, followed by letter, number or underscore
3. Operators
- Arithmetic operators: -, *, /, %
- Relational operators: ==, !=, , =
- Logical operators: &&, ||, !
4. Process control
- if statement: determine whether the condition is true and execute the corresponding code block
- switch statement: select different code blocks according to the variable value to execute
- for loop: Repeat code blocks for a specific number of times
- while loop: Repeat the code block until the condition is false
V. Function
- Define function: return_type function_name(parameter_list);
- Call function: function_name(argument_list);
6. Array
- Declare array: data_type array_name[size];
- Access array elements: array_name[index]
7. Character string
- Declare string: char string_name[];
- Commonly used functions of strings: strcpy(), strcat(), strlen()
8. Pointer
- Definition pointer: data_type *pointer_name;
- Access the value pointed to by the pointer: *pointer_name
- Pointer operation: ,-, , --
9. Structure
- Define structure: struct structure_name { data_type member_name; };
- Access structure member: structure_name.member_name
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