npm install binary-search-tree --save

make test

var BinarySearchTree = require('binary-search-tree').BinarySearchTree
  , AVLTree = require('binary-search-tree').AVLTree   // Same API as BinarySearchTree

// Creating a binary search tree
var bst = new BinarySearchTree();

// Inserting some data
bst.insert(15, 'some data for key 15');
bst.insert(12, 'something else');
bst.insert(18, 'hello');

// You can insert multiple pieces of data for the same key
// if your tree doesn't enforce a unique constraint
bst.insert(18, 'world');

// Retrieving data (always returned as an array of all data stored for this key)
bst.search(15);   // Equal to ['some data for key 15']
bst.search(18);   // Equal to ['hello', 'world']
bst.search(1);    // Equal to []

// Search between bounds with a MongoDB-like query
// Data is returned in key order
// Note the difference between $lt (less than) and $gte (less than OR EQUAL)
bst.betweenBounds({ $lt: 18, $gte: 12});   // Equal to ['something else', 'some data for key 15']

// Deleting all the data relating to a key
bst.delete(15);   // bst.search(15) will now give []
bst.delete(18, 'world');   // bst.search(18) will now give ['hello']

var bst = new BinarySearchTree({ unique: true });
bst.insert(10, 'hello');
bst.insert(10, 'world');   // Will throw an error

// Custom key comparison function
// It needs to return a negative number if a is less than b,
// a positive number if a is greater than b
// and 0 if they are equal
// If none is provided, the default one can compare numbers, dates and strings
// which are the most common usecases
function compareKeys (a, b) {
  if (a.age < b.age) { return -1; }
  if (a.age > b.age) { return 1; }

  return 0;
}

// Now we can use objects with an 'age' property as keys
var bst = new BinarySearchTree({ compareKeys: compareKeys });
bst.insert({ age: 23 }, 'Mark');
bst.insert({ age: 47 }, 'Franck');

// Custom value equality checking function used when we try to just delete one piece of data
// Returns true if a and b are considered the same, false otherwise
// The default function is able to compare numbers and strings
function checkValueEquality (a, b) {
  return a.length === b.length;
}
var bst = new BinarySearchTree({ checkValueEquality: checkValueEquality });
bst.insert(10, 'hello');
bst.insert(10, 'world');
bst.insert(10, 'howdoyoudo');

bst.delete(10, 'abcde');
bst.search(10);   // Returns ['howdoyoudo']