/
queue.js
80 lines (56 loc) · 1.09 KB
/
queue.js
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/**
* Queue is a type of list where data are inserted at the end
* and are removed from the from. [FIFO]
*/
export class Queue {
/**
* Creates an instance of Queue.
*/
constructor() {
// stores the queue elements
this.dataStore = [];
}
/**
* Adds an element to the end of a queue.
*
* @param {(number|string|object)} element - a new element.
*/
enqueue( element ) {
this.dataStore.push( element );
}
/**
* Removes an element from the front of a queue.
*/
dequeue() {
return this.dataStore.shift();
}
/**
* Returns the front element of a queue.
*/
front() {
return this.dataStore[ 0 ];
}
/**
* Returns the back element of a queue.
*/
back() {
return this.dataStore[ this.dataStore.length - 1 ];
}
/**
* Checks if a queue is empty.
*/
isEmpty() {
return ( this.dataStore.length === 0 );
}
/**
* Returns the length of a queue.
*/
length() {
return this.dataStore.length;
}
/**
* [Optional]. Returns the string representation of a queue.
*/
toString() {
}
}