add reverse a linked list

Author: akgmage

Linked List/reverse_linked_list.go

@@ -0,0 +1,61 @@
+package main
+
+import "fmt"
+
+// ListNode represents a node in the linked list
+type ListNode struct {
+    Val  int
+    Next *ListNode
+}
+
+// ReverseListIteratively reverses a linked list iteratively
+func ReverseListIteratively(head *ListNode) *ListNode {
+    var prev, curr *ListNode
+    curr = head
+
+    for curr != nil {
+        nextTemp := curr.Next
+        curr.Next = prev
+        prev = curr
+        curr = nextTemp
+    }
+
+    return prev
+}
+
+// ReverseListRecursively reverses a linked list recursively
+func ReverseListRecursively(head *ListNode) *ListNode {
+    if head == nil || head.Next == nil {
+        return head
+    }
+
+    newHead := ReverseListRecursively(head.Next)
+    head.Next.Next = head
+    head.Next = nil
+
+    return newHead
+}
+
+func main() {
+    // Create a linked list: 1 -> 2 -> 3 -> 4 -> 5
+    head := &ListNode{1, &ListNode{2, &ListNode{3, &ListNode{4, &ListNode{5, nil}}}}}
+
+    // Reverse the linked list iteratively
+    reversedListIteratively := ReverseListIteratively(head)
+    fmt.Println("Reversed linked list (iteratively):")
+    for reversedListIteratively != nil {
+        fmt.Printf("%d ", reversedListIteratively.Val)
+        reversedListIteratively = reversedListIteratively.Next
+    }
+    fmt.Println()
+
+	head = &ListNode{1, &ListNode{2, &ListNode{3, &ListNode{4, &ListNode{5, nil}}}}}
+    // Reverse the linked list recursively
+    reversedListRecursively := ReverseListRecursively(head)
+    fmt.Println("Reversed linked list (recursively):")
+    for reversedListRecursively != nil {
+        fmt.Printf("%d ", reversedListRecursively.Val)
+        reversedListRecursively = reversedListRecursively.Next
+    }
+    fmt.Println()
+}