The java.util.ArrayDeque.addFirst(Object element) method in Java is used to insert a specific element at the front of this deque.
Parameters: The parameter element is of the type ArrayDeque and refers to the element to be added.
Return Value: The function does not return any value.
Exceptions: The method throws NullPointerException if the passed parameter is NULL.
Below programs illustrate the Java.util.ArrayDeque.addFirst() method:
ArrayDeque: [10, 15, 30, 20, 5] ArrayDeque_front_addition: [70, 60, 50, 40, 10, 15, 30, 20, 5] Final ArrayDeque: [70, 60, 50, 40, 10, 15, 30, 20, 5, 1, 2, 3]
ArrayDeque: [Welcome, To, Geeks, 4, Geeks] ArrayDeque_front_addition: [Hello, World, GFG, Welcome, To, Geeks, 4, Geeks] Final ArrayDeque: [Hello, World, GFG, Welcome, To, Geeks, 4, Geeks, Coding, At, BEST]
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