vector :: cbegin() and vector :: cend() in C++ STL

Vectors are known as dynamic arrays which can change its size automatically when an element is inserted or deleted. This storage is maintained by container.

vector::cbegin()

The function returns an iterator which is used to iterate container.

  • The iterator points to the beginning of the vector.
  • Iterator cannot modify the contents of the vector.

Syntax:

vectorname.cbegin()

Parameters:
There is no parameter

Return value:
Constant random access iterator points to the beginning of the vector.

Exception:
No exception

Below program(s) illustrate the working of the function

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// CPP program to illustrate
// use of cbegin()
#include <iostream>
#include <string>
#include <vector>
  
using namespace std;
  
int main()
{
    vector<string> vec;
  
    // 5 string are inserted
    vec.push_back("first");
    vec.push_back("second");
    vec.push_back("third");
    vec.push_back("fourth");
    vec.push_back("fifth");
  
    // displaying the contents
    cout << "Contents of the vector:" << endl;
    for (auto itr = vec.cbegin(); 
         itr != vec.end(); 
         ++itr)
        cout << *itr << endl;
  
    return 0;
}

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Output:

Contents of the vector:
first
second
third
fourth
fifth
vector::cend()

The function returns an iterator which is used to iterate container.

  • The iterator points to past-the-end element of the vector.
  • Iterator cannot modify the contents of the vector.

Syntax:

vectorname.cend()

Parameters:
There is no parameter

Return value:
Constant random access iterator points to past-the-end element of the vector.

Exception:
No exception

Below program(s) illustrate the working of the function

filter_none

edit
close

play_arrow

link
brightness_4
code

// CPP programto illustrate
// functioning of cend()
#include <iostream>
#include <string>
#include <vector>
  
using namespace std;
  
int main()
{
    vector<string> vec;
  
    // 5 string are inserted
    vec.push_back("first");
    vec.push_back("second");
    vec.push_back("third");
    vec.push_back("fourth");
    vec.push_back("fifth");
  
    // displaying the contents
    cout << "Contents of the vector:" << endl;
    for (auto itr = vec.cend() - 1; 
         itr >= vec.begin(); 
         --itr)
        cout << *itr << endl;
  
    return 0;
}

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Output:

Contents of the vector:
fifth
fourth
third
second
first


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