gods/examples/btree.go

// Copyright (c) 2015, Emir Pasic. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package examples

import (
	"fmt"
	"github.com/emirpasic/gods/trees/btree"
)

// BTreeExample to demonstrate basic usage of BTree
func BTreeExample() {
	tree := btree.NewWithIntComparator(3) // empty (keys are of type int)

	tree.Put(1, "x") // 1->x
	tree.Put(2, "b") // 1->x, 2->b (in order)
	tree.Put(1, "a") // 1->a, 2->b (in order, replacement)
	tree.Put(3, "c") // 1->a, 2->b, 3->c (in order)
	tree.Put(4, "d") // 1->a, 2->b, 3->c, 4->d (in order)
	tree.Put(5, "e") // 1->a, 2->b, 3->c, 4->d, 5->e (in order)
	tree.Put(6, "f") // 1->a, 2->b, 3->c, 4->d, 5->e, 6->f (in order)
	tree.Put(7, "g") // 1->a, 2->b, 3->c, 4->d, 5->e, 6->f, 7->g (in order)

	fmt.Println(tree)
	// BTree
	//         1
	//     2
	//         3
	// 4
	//         5
	//     6
	//         7

	_ = tree.Values() // []interface {}{"a", "b", "c", "d", "e", "f", "g"} (in order)
	_ = tree.Keys()   // []interface {}{1, 2, 3, 4, 5, 6, 7} (in order)

	tree.Remove(2) // 1->a, 3->c, 4->d, 5->e, 6->f (in order)
	fmt.Println(tree)
	// BTree
	//     1
	//     3
	// 4
	//     5
	//     6

	tree.Clear() // empty
	tree.Empty() // true
	tree.Size()  // 0

	// Other:
	tree.Height()     // gets the height of the tree
	tree.Left()       // gets the left-most (min) node
	tree.LeftKey()    // get the left-most (min) node's key
	tree.LeftValue()  // get the left-most (min) node's value
	tree.Right()      // get the right-most (max) node
	tree.RightKey()   // get the right-most (max) node's key
	tree.RightValue() // get the right-most (max) node's value
}