Singly Linked List – Traversal Operation

Traversal Operation in Singly Linked List

Traversal in a singly linked list means visiting each node from the head (first node) to the last node, one-by-one using the next pointer.

This operation is commonly used when searching, printing, or performing any action on each element in the list.

Visual Example

Suppose we have the following linked list:

Detailed Step-by-Step Traversal

Initialize a pointer: Create a pointer variable named current and assign it to the head of the list. This means current now points to the first node which has value 5.
Step 1:
- Check if current is not null. It points to node with value 5.
- Visit this node. For example, you can print(current.data) or perform any other logic using its value.
- Move to the next node: current = current.next. Now current points to node with value 15.
Step 2:
- current points to node with value 15.
- Process the data — e.g., print 15.
- Move to next: current = current.next. Now current points to node with value 25.
Step 3:
- current points to node with value 25.
- Process the data — e.g., print 25.
- Move to next: current = current.next. Now current points to node with value 35.
Step 4:
- current points to node with value 35.
- Process the data — e.g., print 35.
- Move to next: current = current.next. Now current becomes null.
End of traversal:
- current is now null, which means we’ve reached the end of the list.
- Exit the traversal loop.

This process ensures that every node is visited exactly once, following the direction of the next pointers until the list ends.

Complete Pseudocode: Traverse a Singly Linked List

This pseudocode shows how to traverse a singly linked list and print each node’s value.

function traverseList(head):
    curr = head
    while curr is not null:
        print(curr.value)
        curr = curr.next

Let’s walk through each part of the code to understand how the list is traversed.

function traverseList(head):
    curr = head

Explanation: We define a function that takes the head of the list and uses a pointer curr to keep track of the current node.

    while curr is not null:
        print(curr.value)
        curr = curr.next

Explanation: We loop until we reach the end of the list. For each node, we print its value and then move to the next node. The traversal stops when curr becomes null.