Add Tree level-order traversal in golang

Tree_Levelorder_Traversal/Tree_Levelorder_Traversal.go

@@ -0,0 +1,103 @@
+package main
+
+import (
+	"fmt"
+)
+
+// Queue represents the queue
+type Queue struct {
+	front *QueueNode
+	rear  *QueueNode
+	size  int
+}
+
+// QueueNode struct represents the nodes present in the Queue
+type QueueNode struct {
+	Node BinaryTreeNode
+	next *QueueNode
+}
+
+// BinaryTreeNode represents the nodes of the tree
+type BinaryTreeNode struct {
+	data  int
+	left  *BinaryTreeNode
+	right *BinaryTreeNode
+}
+
+func (q *Queue) enqueue(n *BinaryTreeNode) {
+	newNode := QueueNode{
+		Node: *n,
+		next: nil,
+	}
+
+	if q.size == 0 {
+		q.front = &newNode
+		q.rear = &newNode
+	} else {
+		q.rear.next = &newNode
+		q.rear = q.rear.next
+	}
+	q.size++
+}
+
+func (q *Queue) dequeue() *BinaryTreeNode {
+	if q.size == 0 {
+		return nil
+	}
+
+	n := q.front.Node
+	q.size--
+
+	if q.size > 0 {
+		q.front = q.front.next
+	} else {
+		q.front = nil
+		q.rear = nil
+	}
+
+	return &n
+
+}
+
+func (q *Queue) isEmpty() bool {
+	if q.size == 0 {
+		return true
+	}
+	return false
+}
+
+func newNode(i int) *BinaryTreeNode {
+	return &BinaryTreeNode{
+		data: i,
+	}
+}
+
+// PrintLevelorder prints the Level Order Traversal of the tree
+func (nptr *BinaryTreeNode) PrintLevelorder() {
+	if nptr == nil {
+		return
+	}
+
+	q := Queue{}
+	q.enqueue(nptr)
+	for q.size > 0 {
+		currentptr := q.dequeue()
+		if currentptr.left != nil {
+			q.enqueue(currentptr.left)
+		}
+		if currentptr.right != nil {
+			q.enqueue(currentptr.right)
+		}
+		fmt.Print(currentptr.data, " ")
+	}
+}
+
+func main() {
+	root := newNode(1)
+	root.left = newNode(2)
+	root.right = newNode(3)
+	root.left.left = newNode(4)
+	root.left.right = newNode(5)
+	root.right.right = newNode(6)
+	root.PrintLevelorder()
+}