lctree

README

lctree 🌱

lctree provides a CLI and Golang primitives to serialize and deserialize LeetCode binary trees (e.g. "[5,4,7,3,null,2,null,-1,null,9]").

Overview   |   Getting Started   |   Contributing   

Overview

• Deserialize/Serialize
• Walk Depth-First
• Walk Breadth-First
• Convert to DOT language for visualization
• CLI (see bin/)

Getting Started

Deserialize

package main

import (
	"fmt"

	"github.com/sbourlon/go-lctree"
)

// Type alias
type TreeNode = lctree.TreeNode

func mySolution(root *TreeNode) {
	fmt.Printf("root: %+v\n", root)
	return
}

func main() {
	tree := lctree.Deserialize("[1,null,2,3]")
	mySolution(tree)
}

Output:

root: &{Val:1 Left:<nil> Right:0xc00008e020}

Serialize

package main

import (
	"fmt"

	"github.com/sbourlon/go-lctree"
)

type TreeNode = lctree.TreeNode

func mySolution() *TreeNode {
	return lctree.Deserialize("[1,null,2,3]")
}

func main() {
	tree := mySolution()
	fmt.Println(lctree.Serialize(tree))
}

Output:

[1,null,2,3]

Walk Depth-First

package main

import (
	"fmt"

	"github.com/sbourlon/go-lctree"
)

type TreeNode = lctree.TreeNode

func mySolution() *TreeNode {
	return lctree.Deserialize("[1,null,2,3]")
}

func main() {
	tree := mySolution()

	walkFn := func(n *TreeNode) error {
		fmt.Printf("%+v\n", n)
		return nil
	}

	tree.WalkDepthFirst(walkFn)
}

Output:

&{Val:1 Left:<nil> Right:0xc00000c0a0}
&{Val:2 Left:0xc00000c0c0 Right:<nil>}
&{Val:3 Left:<nil> Right:<nil>}

Walk Breadth-First

package main

import (
	"fmt"

	"github.com/sbourlon/go-lctree"
)

type TreeNode = lctree.TreeNode

func mySolution() *TreeNode {
	return lctree.Deserialize("[1,null,2,3]")
}

func main() {
	tree := mySolution()

	walkFn := func(n *TreeNode, depth int) error {
		fmt.Printf("depth: %d\t%+v\n", depth, n)
		return nil
	}

	tree.WalkBreadthFirst(walkFn)
}

Output:

depth: 0        &{Val:1 Left:<nil> Right:0xc00000c0a0}
depth: 1        <nil>
depth: 1        &{Val:2 Left:0xc00000c0c0 Right:<nil>}
depth: 2        &{Val:3 Left:<nil> Right:<nil>}
depth: 2        <nil>
depth: 3        <nil>
depth: 3        <nil>

Convert to DOT language for visualization

package main

import (
	"fmt"

	"github.com/sbourlon/go-lctree"
)

type TreeNode = lctree.TreeNode

func mySolution() *TreeNode {
	return lctree.Deserialize("[10,5,15,null,null,6,20]")
}

func main() {
	tree := mySolution()
	fmt.Println(tree.DOT())
}

Output:

digraph {
graph [ordering="out"];
10;
5;
15;
6;
20;
10 -> 5;
10 -> 15;
15 -> 6;
15 -> 20;
}

then convert into a png picture (e.g. tree.png):

$ dot -Tpng -o tree.png tree.dot

Output:

Contributing

Pull-requests, feature requests and issues are welcome.

License

ISC license

Documentation

Overview

Package lctree provides primitives to serialize and deserialize leetcode trees

Index

• func Serialize(t *TreeNode) string
• type TreeNode
  • func Deserialize(tree string) *TreeNode
  • func (t *TreeNode) DOT() string
  • func (t *TreeNode) WalkBreadthFirst(fn WalkBFFn) error
  • func (t *TreeNode) WalkDepthFirst(fn WalkFn) error
• type WalkBFFn
• type WalkFn

Functions

func Serialize

func Serialize(t *TreeNode) string

Serialize converts a TreeNode tree into a leetcode serialized tree

Types

type TreeNode

type TreeNode struct {
	Val   int
	Left  *TreeNode
	Right *TreeNode
}

TreeNode is a node

func Deserialize

func Deserialize(tree string) *TreeNode

Deserialize converts a leetcode serialized tree into a TreeNode tree

func (*TreeNode) DOT

func (t *TreeNode) DOT() string

DOT converts a TreeNode tree into Graphviz DOT See: http://www.graphviz.org/documentation/

func (*TreeNode) WalkBreadthFirst

func (t *TreeNode) WalkBreadthFirst(fn WalkBFFn) error

WalkBreadthFirst traverses the tree breadth-first. fn is called on each visited node

func (*TreeNode) WalkDepthFirst

func (t *TreeNode) WalkDepthFirst(fn WalkFn) error

WalkDepthFirst traverses the tree depth-first. fn is called on each visited node

type WalkBFFn

type WalkBFFn func(n *TreeNode, depth int) error

WalkBFFn is the signature of the function called on each node by the function WalkBreadthFirst

type WalkFn

type WalkFn func(n *TreeNode) error

WalkFn is the signature of the function called on each node visited by the function WalkDepthFirst