What is the time complexity of accessing an element in a linked list by index?
Practice Questions
Q1
What is the time complexity of accessing an element in a linked list by index?
O(1)
O(n)
O(log n)
O(n log n)
Questions & Step-by-Step Solutions
What is the time complexity of accessing an element in a linked list by index?
Step 1: Understand what a linked list is. A linked list is a data structure where each element (node) points to the next one.
Step 2: Know that each node in a linked list contains data and a reference (or pointer) to the next node.
Step 3: Realize that to access an element by index, you need to start from the first node (head) of the linked list.
Step 4: Count each node as you move from the head to the desired index. This means you have to go through each node one by one.
Step 5: If the index is 'n', you will have to traverse 'n' nodes to reach that index.
Step 6: Therefore, the time it takes to access an element by index in a linked list is proportional to the number of nodes you have to traverse, which is 'n'.
Step 7: This is why we say the time complexity is O(n).