Set: Set data structure allow to add data to a container.

This custom Set implementation in JavaScript uses an array (collection[]) to store unique values, similar to the built-in Set object. It provides methods to add, remove, check, and retrieve the size of the collection while ensuring each element is unique.

Methods:

• size(): Returns the number of elements in the set.
• has(item): Checks if the set contains a specific item.
• add(item): Adds a new item to the set if it doesn’t already exist.
• delete(item): Removes an item from the set if it exists.
• clear(): Removes all items from the set.
• values(): Returns all the items in the set.

Here is an example of set internal implementation.

const Set=function(){
  let collection=[];
  this.size=function(){
    return collection.length;
  }
  this.has=function(item){
   return collection.indexOf(item)!==-1
  }
  this.add=function(item){
    if(!this.has(item)){
      collection.push(item)
      return true;
    }
    return false;
  }
  this.delete=function(item){
    if(!this.has(item)){
      return false;
    }else{
      let index=collection.indexOf(item);
      collection.splice(index,1);
      return true;
    }
  }
  this.clear=function(){
    collection=[];
  }
  this.values=function(){
    return collection;
  }
}
let set=new Set();
console.log(set.size());
console.log(set.add(1));
console.log(set.add(2));
console.log(set.size());
console.log(set.delete(2));
console.log(set.delete(2));
console.log(set.size());

Time Complexity:

• size(): O(1) - Simply returns the length of the array.
• has(item): O(n) - The indexOf() method is used, which performs a linear search through the array.
• add(item): O(n) - Before adding, it calls has(item) which is O(n), and if the item doesn’t exist, push() is O(1).
• delete(item): O(n) - It uses indexOf() to find the index of the item, which is O(n), and then splice() to remove it, which is also O(n).
• clear(): O(1) - Just resets the array to an empty array.
• values(): O(1) - Returns the reference to the array. > Any comments or suggestions are welcome.