collections

The collections module provides advanced data structures and algorithms.

Import

import collections
import { Queue, Stack, LinkedList } from collections

Linked List

@import collections#LinkedList

@list = @LinkedList<Int>::new()
@list#push_front(1)
@list#push_back(2)
@list#push_back(3)
@value = @list#pop_front()  @// 1
@list#length  @// 2

Methods

Method	Description
new()	Create new list
push_front(val)	Add to front
push_back(val)	Add to back
pop_front()	Remove from front
pop_back()	Remove from back
peek_front()	View front
peek_back()	View back
insert_at(idx, val)	Insert at index
remove_at(idx)	Remove at index
length	Get length
is_empty	Check if empty

Stack

@import collections#Stack

@stack = @Stack<Int>::new()
@stack#push(1)
@stack#push(2)
@stack#push(3)
@top = @stack#peek()    @// 3
@value = @stack#pop()   @// 3
@stack#is_empty         @// false
@stack#length           @// 2

Methods

Method	Description
new()	Create new stack
push(val)	Push value
pop()	Pop value
peek()	View top
length	Get size
is_empty	Check if empty

Queue

@import collections#Queue

@queue = @Queue<String>::new()
@queue#enqueue("first")
@queue#enqueue("second")
@queue#enqueue("third")
@value = @queue#dequeue()  @// "first"
@queue#peek()              @// "second"
@queue#length              @// 2

Methods

Method	Description
new()	Create new queue
enqueue(val)	Add to back
dequeue()	Remove from front
peek()	View front
length	Get size
is_empty	Check if empty

Priority Queue

@import collections#PriorityQueue

@pq = @PriorityQueue<Task>::new()
@pq#push("low", 1)
@pq#push("high", 10)
@pq#push("medium", 5)
@value = @pq#pop()  @// "high" (highest priority)

Deque (Double-ended Queue)

@import collections#Deque

@deque = @Deque<Int>::new()
@deque#push_front(1)
@deque#push_back(2)
@deque#push_front(0)
@deque#pop_back()     @// 2
@deque#pop_front()    @// 0

HashSet

@import collections#HashSet

@set = @HashSet<Int>::new()
@set#add(1)
@set#add(2)
@set#add(3)
@set#contains(2)   @// true
@set#remove(2)
@set#length        @// 2

Set Operations

@a = @HashSet<Int>::from([1, 2, 3])
@b = @HashSet<Int>::from([2, 3, 4])

@a#union(@b)          @// {1, 2, 3, 4}
@a#intersection(@b)   @// {2, 3}
@a#difference(@b)     @// {1}

HashMap

@import collections#HashMap

@map = @HashMap<String, Int>::new()
@map#insert("one", 1)
@map#insert("two", 2)
@value = @map#get("one")   @// Option<Int>
@map#contains_key("one")   @// true
@map#remove("one")
@map#length                @// 1

TreeMap (Sorted Map)

@import collections#TreeMap

@tree = @TreeMap<String, Int>::new()
@tree#insert("c", 3)
@tree#insert("a", 1)
@tree#insert("b", 2)
@keys = @tree#keys()  @// ["a", "b", "c"] (sorted)

Binary Tree

@import collections#BinaryTree

@tree = @BinaryTree<Int>::new()
@tree#insert(5)
@tree#insert(3)
@tree#insert(7)
@tree#contains(3)  @// true

Traversal

@tree#in_order()     @// [3, 5, 7]
@tree#pre_order()    @// [5, 3, 7]
@tree#post_order()   @// [3, 7, 5]
@tree#level_order()  @// [5, 3, 7]

Heap

@import collections#Heap

@heap = @Heap<Int>::new()
@heap#push(3)
@heap#push(1)
@heap#push(2)
@min = @heap#pop()  @// 1 (min-heap)

Max Heap

@max_heap = @Heap<Int>::new_max()
@max_heap#push(3)
@max_heap#push(1)
@max_heap#push(2)
@max = @max_heap#pop()  @// 3

Trie

@import collections#Trie

@trie = @Trie::new()
@trie#insert("hello")
@trie#insert("help")
@trie#insert("world")
@trie#contains("hello")   @// true
@trie#starts_with("hel")  @// true
@trie#autocomplete("hel") @// ["hello", "help"]

Algorithms

Sorting

@import collections#sort

@arr = [3, 1, 4, 1, 5, 9, 2, 6]
@sorted = @sort#quick(@arr)
@// [1, 1, 2, 3, 4, 5, 6, 9]

Available sorts: quick, merge, heap, insertion, bubble.

Searching

@import collections#search

@arr = [1, 2, 3, 4, 5]
@search#linear(@arr, 3)   @// 2
@search#binary(@arr, 3)   @// 2