Why is the remove method faster in the linked list than in an array?

1.	Why is the remove method faster in the linked list than in an array?
Answer» In the linked list, we only need to adjust the references when we want to delete the element from either end or the front of the linked list. But in the array, INDEXES are used. So to manage proper indexing, we need to adjust the values from the array So this adjustment of value is COSTLIER than the adjustment of references. Example - To Delete from the front of the linked list, internally the references adjustments happened LIKE this. The only THING that will change is that the head pointer will point to the head’s next node. And delete the previous node. That is the constant time operation. Whereas in the ArrayList, internally it should work like this- For DELETION of the first element, all the next element has to move to one place ahead. So this copying value takes time. So that is the reason why removing in ArrayList is slower than LinkedList.

Answer»

In the linked list, we only need to adjust the references when we want to delete the element from either end or the front of the linked list. But in the array, INDEXES are used. So to manage proper indexing, we need to adjust the values from the array So this adjustment of value is COSTLIER than the adjustment of references.

Example - To Delete from the front of the linked list, internally the references adjustments happened LIKE this.

The only THING that will change is that the head pointer will point to the head’s next node. And delete the previous node. That is the constant time operation.

Whereas in the ArrayList, internally it should work like this-

For DELETION of the first element, all the next element has to move to one place ahead. So this copying value takes time. So that is the reason why removing in ArrayList is slower than LinkedList.

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