Linked ListBeginner
Linked List Reversal
Reverse a linked list (or sublist) by reassigning next pointers while traversing.
Problem: Reverse Linked List
Reverse a singly linked list [1, 2, 3, 4, 5] in-place using three pointers.
1
curr
2
3
4
5
null
PrevCurrNext
Initialize: prev = null, curr = 1
Start with prev = null and curr at head (1). Will reverse pointers one by one.
Step 1/8
Speed:
When to Use
- Reverse entire linked list
- Reverse k-group or sublist
- Palindrome linked list
Key Indicators
- Reverse linked list
- Reorder nodes
- Palindrome check on list
Complexity
Time
O(n)
Space
O(1)
Common Problems
Reverse Linked ListReverse Linked List IIPalindrome Linked ListReverse Nodes in k-Group
Code
prev = null, current = head
while current:
next = current.next
current.next = prev
prev = current
current = next
return prevWant all 29 patterns with detailed visual walkthroughs?
The complete book includes 84 practice problems, full decision tree, and illustrated step-by-step solutions.
Book Coming Soon ($4.99)