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

 

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bool empty() const;

Checks if the underlying container has no elements. Equivalent to: return c.empty().

Parameters

(none)

Return value

true if the underlying container is empty, false otherwise.

Complexity

Constant.

Example

Run this code

#include <cassert>
#include <queue>
 
int main()
{
    std::queue<int> queue;
    assert(queue.empty());
 
    queue.push(42);
    assert(!queue.empty());
 
    queue.pop();
    assert(queue.empty());
}

See also

size	returns the number of elements (public member function)
empty (C++17)	checks whether the container is empty (function template)