Content of the Standard Template Library
- Standard template classes: complex numbers, sequential pairs
- Iterators
- Standard containers: vectors, tables, stacks, queues, sets, mappings, etc.
- Standard algorithms: Find, sort, etc.
How to use the Standard Template library style
- "<>": Template name < data object base type > data object name;
- Example 1:complex<double>a (1.0,2.0);
- Example 2:pair<string,string>name ("Zhang", "san");(sequence puppet)
- Example 3:vector<int>v (8);
Plural
General description
- Header file: "Complex"
- Template name:complex<>
- Base type: Float,double,long double
- Preferred Double,float low precision, long double deprecated
Real part and imaginary part
member functions Real () and Imag ()
Complex operations
Complex numbers all operate in a mathematical format
Cout,cin, all overloaded; in the format (REAL,IMAG)
Sequential couple
General description
- Header file: "Utility"
- Template name:pair<>
- Used to represent two objects that always appear paired
- Example 1:pair<int,double>a (1,1.0);
- Example 2:pair<string,string>name ("Zhang", "San");
Usage rules
- Data members Exposed: First,second
- Example: cout << name.first << "," << Name.second;
- Sequential couple comparison: compare first size, compare second size at same time
- Make_pair: Auxiliary function for constructing order pairs
- Example:pair<int,double> A; A = Make_pair (1,1.0);
Vector
The purpose of the vector
Instead of arrays, you can use vectors like arrays
Use of vectors
- Defines the format:vector<int> V (8);//an element containing 8 integers
- Operator[]: overloaded, using format V[i] access to element I
- Vectors can be assigned as a whole
- Size (): Returns the number of elements in the vector
- Capacity: Returns the maximum number of elements that the vector currently can store
- Clear (): removes all elements of the vector, but does not release the vector itself
- Resize (int newsize): Re-set vector capacity
Iterators
The nature of iterators
- Accessing data Objects in a container through iterators
- Functions like pointers, array indexing: Obtaining the next data object with pointer subtraction and array subscript operations
- An iterator can be a pointer, but it does not have to be a pointer or always use the address of a data object
How to use iterators
- Declaring iterator variables
- Use the leading operator to access the current target object pointed to by the iterator
- Gain access to the next object using the increment operator
- If the new iterator value exceeds the container's element range, a pointer-like value becomes null and the target object is not referenced
Classification of iterators
- Input iterator: Provides read-only access to the object
- Output iterator: Provides write-only access to an object
- Forward iterator: Provides forward (incrementing) read and write access to an object
- Bidirectional iterator: Provides read-write access to the object's forward and reverse (increment and decrement)
- Random Access iterators: Provides random read and write access to objects
C + + Learning Note 32: Generics programming Development 1
