C Language Focus

One, basic data types, variables, constants, operators
1, data type: int, short, char, long, float, double.
2, Constant classification: (1) integer constant (2) floating-point constant (3) character-type constant (4) string constant
3, constant characteristics: constants are stored in the constant area, the constant area cannot be changed.
4. Definition and nature of variables: Data type variable name = initial value. The essence: A variable is a container.
5. Naming conventions for variable names:
6. Operator. (1) Assignment operator = (2) arithmetic operator: +,-, *,/,%, + +,--. (3) compliant operator + =,-=,/=,%=. (4) Relational operators: <, <=,, >=,! =. (5) logical operator: &&, | | , !. Note the && | | Short-circuit phenomenon. (6) Conditional operator? : (7) bitwise operator: &, |, ~, ^, <<, >>;
7. An expression.
8. Basic input and output functions.%d,%o,%0x (%x),%ld,%lu,%c,%f,%s,%p.
Two, branch structure
1, BOOL
The 2,if statement. (1) if (2) if-----Else (3) If-----else if----------
3. Switch-----------case (1) You can only fill in the constant expression (2) if you want to define a variable in the box branch, increase the parentheses (3) Default (4) break
Three, circular structure
1, the four conditions of the loop must: initialization of cyclic variables, cyclic conditions, increment of cyclic variables, loop body; execution flow: 1-2 -4-3-2- -4--2,
2.for Loop---loop nesting
3. While, does---while;
4, for and while, does--while difference;
5. The difference between break and continue.
6. How do I get a number on each of the digits? Utilization/and%;
Four, array
1, the function of the array.
2, the definition of the array. The power of the array is inseparable from the loop;
3, how to take the array element? subscript.
4, traverse; (VIP)
5, bubble sort (VIP) (1) The effect of outer and inner layer (2) inner Layer-1,-I and outer-1, (3) How to sort ascending and descending;
6, character array--string
7, String handler function
Five, array advanced
1, the nature of the two-dimensional array. --array arrays;
six, Structure (VIP)
1, what is the meaning of structure existence? (1) is a custom data type. (2) Different types of data can be stored
2, definition of structure:
3, how to access struct members through struct variables? variables. Member
4,typedef type redefinition.
5, the structure of the nesting.
6, to compare the idea of local acquisition of the whole;
7. Sorting
Seven, function
1. Function of functions.
2, definition of function: (Four forms)
3, the function of the sub-file form (. h Declaration of the stored function. m storage function Implementation)
4, (1) The declaration of the return value type (2) parameter (3) argument (4) function, the function's implementation, the function body, the functions name.
the role of the 5,return keyword. (1) Returns the value of the function to the keynote function (2) to end the execution of the current function.
6, the function is called. Function name + actual argument.
7, nested invocation of function
8, static effect.
7.5 Binary
1, binary conversion
2, bitwise operator
3, the allocation principle of the stack area.
4, ability, (1) Break point, (2) How to see the execution of the program?
Eight. Pointers
1, the function of the pointer.
2. The definition of the pointer .
3, assignment of pointers
4, the pointer to the heavy pointing
nine, pointer advanced.
1, transmit value and address;
2, the relationship between the pointer and the structure body.
3. How to access struct members through struct pointers.
4,const, function.
10 Dynamic memory allocation
1, partition of storage area, heap area,
2, open space in the heap area malloc, Calloc, realloc reclaim space free
3, Mark delete
4, macro.-Precautions for non-parametric macros and macro macros (Viper)
11, function pointer (VVVVVVVVIP)
1, definition of function pointer
2, how to call a function through a function pointer,
3, callback function.
12, review.
1, enumeration
2, conditional compilation #include and #import的区别.

C Language Focus