std::{{{1}}}::begin, std::{{{1}}}::cbegin

 

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iterator begin() noexcept;	(1)	(since {std})
const_iterator begin() const noexcept;	(2)	(since {std})
const_iterator cbegin() const noexcept;	(3)	(since {std})

Returns an iterator to the first element of the {{{1}}}.

If the {{{1}}} is empty, the returned iterator will be equal to end().

Parameters

(none)

Return value

Iterator to the first element.

Complexity

Constant.

Example

Run this code

#include <algorithm>
#include <iostream>
#include <numeric>
#include <string>
#include <list>
 
int main()
{
    std::list<int> nums{1, 2, 4, 8, 16};
    std::list<std::string> fruits{"orange", "apple", "raspberry"};
    std::list<char> empty;
 
    // Print list.
    std::for_each(nums.begin(), nums.end(), [](const int n) { std::cout << n << ' '; });
    std::cout << '\n';
 
    // Sums all integers in the list nums (if any), printing only the result.
    std::cout << "Sum of nums: "
              << std::accumulate(nums.begin(), nums.end(), 0) << '\n';
 
    // Prints the first fruit in the list fruits, checking if there is any.
    if (!fruits.empty())
        std::cout << "First fruit: " << *fruits.begin() << '\n';
 
    if (empty.begin() == empty.end())
        std::cout << "list 'empty' is indeed empty.\n";
}

Output:

1 2 4 8 16
Sum of nums: 31
First fruit: orange
list 'empty' is indeed empty.

See also

endcend	returns an iterator to the end (public member function of std::{{{1}}})
begincbegin (C++11)(C++14)	returns an iterator to the beginning of a container or array (function template)