std::queue<T,Container>::empty
Min standard notice:
Checks if the underlying container has no elements. Equivalent to: returnc.empty().
# Declarations
bool empty() const;
# Return value
true if the underlying container is empty, false otherwise.
# Example
#include <cassert>
#include <queue>
int main()
{
std::queue<int> queue;
assert(queue.empty());
queue.push(42);
assert(!queue.empty());
queue.pop();
assert(queue.empty());
}