Ruby | Queue shift() function

The shift() is an inbuilt function in Ruby returns the element in the front of the queue and removes it from the queue.

Syntax: q_name.shift() Parameters: The function does not takes any element. Return Value: It returns the first element which is at the front of the queue and removes it from the queue.

Example 1: Output:

5
6

Example 2: Output:

12
21

Reference: https://devdocs.io/ruby~2.5/queue#method-i-shift