added circular-linked-list

Author: Dentrax

linked-list-circular-2-traversal/linked-list-circular-2-traversal.go

@@ -0,0 +1,84 @@
+// ====================================================
+// Data-Structures-with-Go Copyright(C) 2017 Furkan Türkal
+// This program comes with ABSOLUTELY NO WARRANTY; This is free software,
+// and you are welcome to redistribute it under certain conditions; See
+// file LICENSE, which is part of this source code package, for details.
+// ====================================================
+
+package main
+
+import "fmt"
+
+type Node struct {
+	data int
+	next *Node
+}
+
+//Returns an initialized list
+func (n *Node) Init() *Node {
+	n.data = -1
+	return n
+}
+
+//Returns an new list
+func New() *Node {
+	return new(Node).Init()
+}
+
+//Returns the first node in list
+func (n *Node) Next() *Node {
+	return n.next
+}
+
+//Returns the last node in list if exist, otherwise returns current
+func (n *Node) Back() *Node {
+	current := n.next
+	for current != nil && current.next != nil {
+		current = current.next
+	}
+	return current
+}
+
+//This function prints contents of linked list starting from the given node
+func printList(n *Node) {
+	for n != nil {
+		fmt.Println(n.data)
+		n = n.next
+	}
+}
+
+func Push(head_ref **Node, new_data int) {
+	//1. Allocate new node
+	new_node := New()
+	temp := *head_ref
+
+	new_node.data = new_data
+	new_node.next = *head_ref
+
+	//2. If linked list is not NULL then set the next of last node
+	if *head_ref != nil {
+		for temp.next != *head_ref {
+			temp = temp.next
+		}
+		temp.next = new_node
+	} else {
+		//For the fist node
+		new_node.next = new_node
+	}
+	//4. Move the head to point to new_node
+	*head_ref = new_node
+}
+
+func main() {
+	//Start with the empty list
+	head := New()
+
+	Push(&head, 12)
+	Push(&head, 56)
+	Push(&head, 2)
+	Push(&head, 11)
+
+	fmt.Println("Created Circular LinkedList is: ")
+
+	printList(head)
+}