- C++ Data Structures
- C++ Basic Input/Output
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- C++ References
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- C++ Strings
- C++ Arrays
- C++ Numbers
- C++ Functions
- C++ Decision Making
- C++ Loop Types
- C++ Operators
- C++ Storage Classes
- C++ Modifier Types
- C++ Constants/Literals
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- C++ Variable Types
- C++ Data Types
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- C++ Basic Syntax
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C++ Object Oriented
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- C++ Encapsulation
- C++ Abstraction
- C++ Polymorphism
- C++ Overloading
- C++ Inheritance
- C++ Classes & Objects
C++ Advanced
- C++ Web Programming
- C++ Multithreading
- C++ Signal Handling
- C++ Preprocessor
- C++ Templates
- C++ Namespaces
- C++ Dynamic Memory
- C++ Exception Handling
- C++ Files and Streams
C++ Useful Resources
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- C++ Standard Library
- C++ STL Tutorial
- C++ Object Oriented
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C++ STL Tutorial
Hope you have already understood the concept of C++ Template which we have discussed earper. The C++ STL (Standard Template Library) is a powerful set of C++ template classes to provide general-purpose classes and functions with templates that implement many popular and commonly used algorithms and data structures pke vectors, psts, queues, and stacks.
At the core of the C++ Standard Template Library are following three well-structured components −
Sr.No | Component & Description |
---|---|
1 | Containers Containers are used to manage collections of objects of a certain kind. There are several different types of containers pke deque, pst, vector, map etc. |
2 | Algorithms Algorithms act on containers. They provide the means by which you will perform initiapzation, sorting, searching, and transforming of the contents of containers. |
3 | Iterators Iterators are used to step through the elements of collections of objects. These collections may be containers or subsets of containers. |
We will discuss about all the three C++ STL components in next chapter while discussing C++ Standard Library. For now, keep in mind that all the three components have a rich set of pre-defined functions which help us in doing comppcated tasks in very easy fashion.
Let us take the following program that demonstrates the vector container (a C++ Standard Template) which is similar to an array with an exception that it automatically handles its own storage requirements in case it grows −
#include <iostream> #include <vector> using namespace std; int main() { // create a vector to store int vector<int> vec; int i; // display the original size of vec cout << "vector size = " << vec.size() << endl; // push 5 values into the vector for(i = 0; i < 5; i++) { vec.push_back(i); } // display extended size of vec cout << "extended vector size = " << vec.size() << endl; // access 5 values from the vector for(i = 0; i < 5; i++) { cout << "value of vec [" << i << "] = " << vec[i] << endl; } // use iterator to access the values vector<int>::iterator v = vec.begin(); while( v != vec.end()) { cout << "value of v = " << *v << endl; v++; } return 0; }
When the above code is compiled and executed, it produces the following result −
vector size = 0 extended vector size = 5 value of vec [0] = 0 value of vec [1] = 1 value of vec [2] = 2 value of vec [3] = 3 value of vec [4] = 4 value of v = 0 value of v = 1 value of v = 2 value of v = 3 value of v = 4
Here are following points to be noted related to various functions we used in the above example −
The push_back( ) member function inserts value at the end of the vector, expanding its size as needed.
The size( ) function displays the size of the vector.
The function begin( ) returns an iterator to the start of the vector.
The function end( ) returns an iterator to the end of the vector.