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std::vector::front

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< cpp‎ | container‎ | vector
Revision as of 19:40, 31 May 2013 by P12bot (Talk | contribs)

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reference front();
const_reference front() const;

Returns a reference to the first element in the container.

Calling front on an empty container is undefined.

Contents

[edit] Parameters

(none)

[edit] Return value

reference to the first element

[edit] Complexity

Constant

[edit] Notes

For a container c, the expression c.front() is equivalent to *c.begin().

[edit] Example

The following code uses front to display the first element of a std::vector<char>:

#include <vector>
#include <iostream>
 
int main()
{
    std::vector<char> letters {'o', 'm', 'g', 'w', 't', 'f'};
 
    if (!letters.empty()) {
        std::cout << "The first character is: " << letters.front() << '\n';
    }  
}

Output:

The first character is o

See also

access the last element
(public member function) [edit]