std::{{{1}}}::empty

 

C++

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Symbols index

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bool empty() const;

Checks if the container has no elements, i.e. whether begin() == end().

Parameters

(none)

Return value

true if the container is empty, false otherwise

Exceptions

noexcept specification:  

noexcept

  

Complexity

Constant

Example

The following code uses empty to check if a std::{{{1}}}<int> contains any elements:

Run this code

#include <{{{1}}}>
#include <iostream>
 
int main()
{
    std::{{{1}}}<int> numbers;
    std::cout << "Initially, numbers.empty(): " << numbers.empty() << '\n';
 
    numbers.push_back(42);
    numbers.push_back(13317); 
    std::cout << "After adding elements, numbers.empty(): " << numbers.empty() << '\n';
}

Output:

Initially, numbers.empty(): 1
After adding elements, numbers.empty(): 0

See also

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