Largest Unique Set of Characters

main.js

/*
write a program that outputs the largest unique set of characters that can be removed 
from this paragraph without letting its length drop below 50. 
For example: [‘H’, ‘i’, ‘!’, ‘ ’]
*/

//Exception based on paragraph length
function ParagraphLengthException(message){
    this.name = "ParagraphLengthException"
    this.message = message; 
}

//Tokenizes string based on specified split character
function tokenize(paragraph,split){
    return paragraph.split(split);
}

//Tokenize and convert string to lowercase
function prepareInput(paragraph,split){
    return tokenize(paragraph,split).join().toLowerCase();
}


//Get largest unique set 
function getLargestUniqueSet(characterArray,minLength){
    
    var result = new Set();
    var limit = characterArray.length - minLength;
    

    if(characterArray.length<minLength) {
        throw new ParagraphLengthException("Original paragraph is less than min length of " + minLength);
    }

    characterArray.forEach((element)=> {
        if(!result.has(element) && limit > 0){
            result.add(element);
            limit--; //Simulate removal of element from original character array. Prevents concurrent traversal/deletion access
        } else if(result.has(element))
        {
            limit--; //Simulate removal of element from original character array. Prevents concurrent traversal/deletion access
        }
    });

    return result;
}


//Output largest unique set
function printSet(uniqueSet)
{
    var uniqueSetString = "";
    uniqueSet.forEach((element)=>{
        uniqueSetString = uniqueSetString + element + " ";
    })
    console.log(uniqueSetString);
}


//Run Program
function Main(){
    //Tokenize and prepare original string input
    var originalParagraph = "If you want to jumpstart the process of talking to us about this role, here’s a little challenge: write a program that outputs the largest unique set of characters that can be removed from this paragraph without letting its length drop below 50.";
    var tokenSplit = " "; //Takes spaces into account. Change to '' in order to include spaces.
    var characterArray = prepareInput(originalParagraph,tokenSplit).split("");

    var largestUniqueSet;

    //Get larges unique set
    try {
        largestUniqueSet = getLargestUniqueSet(characterArray,50);
        printSet(largestUniqueSet); //Output largest unique set
    } catch(exception) {
        console.log(exception.name,":",exception.message);
    }
}

//Run Program
Main();