unordered_set empty() function in C++ STL

The unordered_set::empty is a built-in function in C++ STL which is used to check if an unordered_set container is empty or not. It returns True if the unordered_set container is empty, otherwise it returns False. 

Syntax:

set_name.empty()

Parameters: This function does not accepts any parameter. 

Return Value: It returns a boolean value True if the unordered_set container is empty, else false. 

Below programs illustrate the above function: 

Program 1:

true
false

Program 2:

false

Time complexity: O(1)