import { LinkedList } from './linked-list';

export declare class Queue<T = any> {
    protected _list: LinkedList<T>;
    /**
     * Adds a value to the end of the queue.
     *
     * @param value The value to add to the queue.
     *
     * @timeComplexity `O(1)`
     */
    enqueue(value: T): void;
    /**
     * Removes and returns the value at the front of the queue.
     *
     * @timeComplexity `O(1)`
     *
     * @returns The value at the front of the queue or undefined if the queue
     * is empty.
     */
    dequeue(): T | void;
    /**
     * Returns the value at the front of the queue without removing it.
     *
     * @timeComplexity `O(1)`
     *
     * @returns The value at the front of the queue or undefined if the queue
     * is empty.
     */
    front(): T | void;
    /**
     * Returns the value at the back of the queue without removing it.
     *
     * @timeComplexity `O(1)`
     *
     * @returns The value at the back of the queue or undefined if the queue
     * is empty.
     */
    back(): T | undefined;
    /**
     * Returns the number of elements in the queue.
     *
     * @timeComplexity `O(1)`
     *
     * @returns The number of elements in the queue.
     */
    size(): number;
    /**
     * Returns true if the queue is empty, false otherwise.
     *
     * @timeComplexity `O(1)`
     *
     * @returns True if the queue is empty, false otherwise.
     */
    isEmpty(): boolean;
    /**
     * Removes all elements from the queue.
     *
     * @timeComplexity `O(1)`
     */
    clear(): void;
    /**
     * Creates a copy of the queue.
     *
     * @timeComplexity `O(n)`
     */
    clone(): Queue<T>;
    /**
     * Converts the queue to an array.
     *
     * @timeComplexity `O(n)`
     *
     * @returns An array containing all the values in the queue.
     */
    toArray(): T[];
    /**
     * Creates a queue from an array of values.
     *
     * @timeComplexity `O(n)`
     */
    static fromArray<T>(array: T[]): Queue<T>;
    values(): IterableIterator<T>;
    [Symbol.iterator](): IterableIterator<T>;
}