morris traversal go implementation

morris-traversal.go

package main
    
    import (
    	"fmt"
    )
    
    type TreeNode struct {
    	Val int
    	Left *TreeNode
    	Right *TreeNode
    }
    
    func main() {
    	root := &TreeNode{
    		Val: 1,
    		Left: &TreeNode{
    			Val: 2,
    			Left: &TreeNode{Val: 4},
    			Right: &TreeNode{Val: 5},
    		},
    		Right: &TreeNode{Val: 3},
    	}
    	inorder(root)
    }
    
    func inorder(root *TreeNode) {
    	cur := root
    	for cur != nil {
    		if cur.Left == nil {
    			fmt.Println(cur.Val)
    			cur = cur.Right
    		} else {
    			p := cur.Left
    			for p.Right != nil {
    				p = p.Right
    			}
    			p.Right = cur
    			next := cur.Left
    			cur.Left = nil
    			cur = next
    		}
    	}
    }