std::queue<T,Container>::size

 

C++

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Symbols index

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stack

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std::queue

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queue::empty

queue::size

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swap(std::queue) (C++11)

operator==operator!=operator<operator>operator<=operator>=operator<=> (C++20)

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uses_allocator<std::queue> (C++11)

formatter<std::queue> (C++23)

Deduction guides(C++17)

 

size_type size() const;

Returns the number of elements in the container adaptor. Equivalent to: return c.size().

Parameters

(none)

Return value

The number of elements in the container adaptor.

Complexity

Constant.

Example

Run this code

#include <cassert>
#include <queue>
 
int main()
{
    std::queue<int> queue;
    assert(queue.size() == 0);
 
    const int count = 8;
    for (int i = 0; i != count; ++i)
        queue.push(i);
    assert(queue.size() == count);
}

See also

empty	checks whether the container adaptor is empty (public member function)
sizessize (C++17)(C++20)	returns the size of a container or array (function template)