collections — Stack, Queue, Deque, Counter¶

Classic data structures for common programming tasks.

Import¶

import collections

Stack (LIFO)¶

Function	Description
`collections.stack_new() -> cptr`	Create a new stack
`collections.stack_push(s, value) -> int`	Push a string value
`collections.stack_pop(s) -> str`	Pop the top value
`collections.stack_peek(s) -> str`	Peek at the top value
`collections.stack_size(s) -> int`	Number of elements
`collections.stack_is_empty(s) -> bool`	Check if empty
`collections.stack_free(s) -> int`	Free the stack

Queue (FIFO)¶

Function	Description
`collections.queue_new() -> cptr`	Create a new queue
`collections.queue_enqueue(q, value) -> int`	Add to back
`collections.queue_dequeue(q) -> str`	Remove from front
`collections.queue_peek(q) -> str`	Peek at front
`collections.queue_size(q) -> int`	Number of elements
`collections.queue_is_empty(q) -> bool`	Check if empty
`collections.queue_free(q) -> int`	Free the queue

Deque (Double-ended Queue)¶

Function	Description
`collections.deque_new() -> cptr`	Create a new deque
`collections.deque_push_front(dq, value) -> int`	Add to front
`collections.deque_push_back(dq, value) -> int`	Add to back
`collections.deque_pop_front(dq) -> str`	Remove from front
`collections.deque_pop_back(dq) -> str`	Remove from back
`collections.deque_peek_front(dq) -> str`	Peek at front
`collections.deque_peek_back(dq) -> str`	Peek at back
`collections.deque_size(dq) -> int`	Number of elements
`collections.deque_is_empty(dq) -> bool`	Check if empty
`collections.deque_free(dq) -> int`	Free the deque

Counter¶

Function	Description
`collections.counter_new() -> cptr`	Create a new counter
`collections.counter_add(c, key) -> int`	Increment key by 1
`collections.counter_add_n(c, key, n) -> int`	Increment key by n
`collections.counter_get(c, key) -> int`	Get count for key
`collections.counter_total(c) -> int`	Sum of all counts
`collections.counter_size(c) -> int`	Number of unique keys
`collections.counter_most_common(c, n) -> str`	Top n keys as string
`collections.counter_free(c) -> int`	Free the counter

Examples¶

Stack¶

import collections

def main() -> int:
    let s = collections.stack_new()
    collections.stack_push(s, "a")
    collections.stack_push(s, "b")
    collections.stack_push(s, "c")

    print(collections.stack_size(s))   # 3
    print(collections.stack_pop(s))    # c
    print(collections.stack_peek(s))   # b
    collections.stack_free(s)
    0

Queue¶

import collections

def main() -> int:
    let q = collections.queue_new()
    collections.queue_enqueue(q, "first")
    collections.queue_enqueue(q, "second")

    print(collections.queue_dequeue(q))  # first
    print(collections.queue_dequeue(q))  # second
    collections.queue_free(q)
    0

Counter¶

import collections

def main() -> int:
    let c = collections.counter_new()
    collections.counter_add(c, "apple")
    collections.counter_add(c, "banana")
    collections.counter_add_n(c, "apple", 2)

    print(collections.counter_get(c, "apple"))   # 3
    print(collections.counter_get(c, "banana"))   # 1
    print(collections.counter_total(c))            # 4
    print(collections.counter_most_common(c, 2))   # apple:3,banana:1
    collections.counter_free(c)
    0