golang_binary_tree.go

package main

import "fmt"

func main() {
    fmt.Println("Welcome to B-Tree test")
    btree := makeBTree()
    fmt.Println("In-order b-tree traversal")
    traverse(&btree)
    fmt.Println("Exit B-Tree test")
    
}

type Node struct {
    value int
    leftChild *Node
    rightChild *Node
}

func makeBTree() Node {
    fmt.Println("Making binary tree ...")
    // level 0 - root
    // 0
    root := Node{0, nil, nil}
    
    // level 1
    //  0
    // 1 2
    root.leftChild = &Node{1, nil, nil}
    root.rightChild = &Node{2, nil, nil}
    
    // level 2
    //     0
    //   1 . 2
    // 3  4 5 . 6
    l2l := root.leftChild
    l2l.leftChild = &Node{3, nil, nil}
    l2l.rightChild = &Node{4, nil, nil}
    
    l2r := root.rightChild
    l2r.leftChild = &Node{5, nil, nil}
    l2r.rightChild = &Node{6, nil, nil}
    
    // level 3
    //       0
    //     1 . 2
    //   3  4 5 . 6
    
    fmt.Println("Made binary tree!")
    
    return root
}

func traverse(tree *Node) {
    if tree == nil {
        return
    }
    
    fmt.Printf("%d ", tree.value)
    if tree.leftChild != nil {
        traverse(tree.leftChild)
    }
    
    if tree.rightChild != nil {
        traverse(tree.rightChild)
    }
}