OC learn the necessary knowledge points of C language

OC Learn the necessary knowledge points of C language

One, basic data types: variables, constants, operators
1. Data type: int, short, char,long (relative to the number of operating systems), float, double,
2, the classification of constants. (1) Integer constant (2) floating-point constant (3) character constant (4) string constant
3. Constants: Constants are stored in a constant area, and the contents of the constant area cannot be changed.
4. Definition and nature of variables: data type, variable name = initial value. An essential variable is a container
5. Naming conventions for variable names:
6. Operator: (1) Assignment operator = (2) arithmetic operator (+ '-' */% + +--) (3) compound operator (+ =-+%= *=/=)
(4) Relational operators > >= < <=! = = = (5) Logical operators && logical AND logical or short-circuit phenomena (logic with front false back not judged)
(6) conditional operator?   : if (?) Else (:)  (7) bitwise operator &, | ^ ~ << >>
7, Expression
8, basic input and output function%d,%o,%0x (%x or%x),%ld,%lu,%c,%s,%f,%p,

Two, branch structure
1, BOOL
2, if statement. (1) if (2) If--else (3) if-else-if-
3,switch-case (1) Case integer constant expression (2) if you want to define a variable in a branch of the box, increase the parentheses (3) Default (4) break

three-cycle structure
1, 4 conditions for loop prerequisites, (1) loop variable initialization (2) loop condition (3) loop variable increment (4) loop condition 1-2-4-3 -2-4-3-------
2,for loop-loop nesting
3, while and Do-while
4, the difference between for and while and do--while. While vs. Do-while
5,continue, break
6, how to get all the digits? Use good/and%

Four Arrays
1. The function of the array .
2. Array definition, the power of the array and the loop is inseparable
3. How do I take an array element? subscript
4. Traversal. (VIP)
5. Bubble sort (VIP) (1) Effect of outer and inner layer (2) inner Layer-1,-I and outer-1 effect (3) How descending ascending
6, character array--string
7, String handler function

Five. Array Advanced
1, the essence of a two-dimensional array ——— array of arrays.

six. Structure (VVVIP)
1. What is the meaning of the existence of the structure? (1) is a custom data type. (2) Different types of data can be stored
2. Definition of structure
3. How do I access struct members through struct variables? variables. Members (points ...)
4.typedef type redefinition
5. Nesting of structural bodies.
6. Compare the idea of partial acquisition of the whole
7. Ascending ascending age by grade
Seven Functions
1. Function of functions.
2. Definition of function (four-medium form)
3. The function of the sub-file form. (. h Description of the storage function. Implementation of the M storage function)
4. (1) return value type (2) The concept of formal parameters (3) The concept of arguments (4) function declaration, function implementation, function body, functional name
the role of the 5.return keyword (1) Returns the value of the function to the main key function (2) to end the execution of the current function
6. Function call, function name + formal parameter
7. Nested calls to Functions
8.static function.
7.5. Binary
1. Binary conversion.
2. Bitwise operators
3. The memory allocation principle of the stack area.
4. Ability. (1) Break point (2) How to see the execution of the program?
Eight hands
1. The role of pointers
2. The definition of the pointer .
3. Assignment of pointers .
4. The pointer is pointing back
Nine Pointer Advanced
1. Transmitting and transmitting values
2. The relationship between the pointer and the structure
3. How do I access struct members through struct pointers? ———— >>> ——— >>>
4.const function
10 allocation of dynamic memory
1. Partition of the storage area. Heap Area
2. Open space in the heap area. malloc, Calloc, ReAlloc, reclaim space: free
3. Mark Delete.
4. Macros--non-parametric macros and macro-considerations (VVVVVIP)
11 function pointer (VVVVIP)
1. Definition of function pointers
2. How to call a function through a function pointer
3. Callback function
12 Reviews
1. Attitude towards Life
2. Enum. Enum
3. Conditional compilation. #include #import的区别

OC learn the necessary knowledge points of C language