freeCodeCamp Challenge Guide: Perform a Union on Two Sets

Perform a Union on Two Sets


Solutions

Solution 1 (Click to Show/Hide)
function Set() {
    var collection = [];

    this.has = function(element) {
        return (collection.indexOf(element) !== -1);
    };

    this.values = function() {
        return collection;
    };

    this.add = function(element) {
        if(!this.has(element)){
            collection.push(element);
            return true;
        }
        return false;
    };

    this.remove = function(element) {
        if(this.has(element)){
           var index = collection.indexOf(element);
            collection.splice(index,1);
            return true;
        }
        return false;
    };

    this.size = function() {
        return collection.length;
    };

    this.union = function(anotherSet){
        const newSet = new Set();
        const addToSet = el => newSet.add(el);
        this.values().forEach(addToSet);
        anotherSet.values().forEach(addToSet);
        return newSet;
    };
}
Solution 2 (Click to Show/Hide)
class Set {
  constructor() {
    this.dictionary = {};
    this.length = 0;
  }

  has(element) {
    return this.dictionary[element] !== undefined;
  }

  values() {
    return Object.keys(this.dictionary);
  }

  add(element) {
    if (!this.has(element)) {
      this.dictionary[element] = true;
      this.length++;
      return true;
    }

    return false;
  }

  remove(element) {
    if (this.has(element)) {
      delete this.dictionary[element];
      this.length--;
      return true;
    }

    return false;
  }

  size() {
    return this.length;
  }

  union(set) {
    const newSet = new Set();
    this.values().forEach(value => {
      newSet.add(value);
    })
    set.values().forEach(value => {
      newSet.add(value);
    })

    return newSet;
  }
}