Tukukkk

I'm learning javascript and have written a function that accepts a string and returns the first word with the greatest number of repeated letters. For example:

Input:"Hello apple pie" - Output:"Hello"

Input:"Hello apple pie yelllow" - Output:"yelllow"

I've tried to keep it as concise as possible. I wonder whether later on in the code it starts to become more verbose. The answer it returns seems to be correct for all tests.

Could someone give some advice about improving my code? Or is it not bad? And any tips about improving readability? Thanks for any help here.

function whichWord(str) {



// 1. split into array with words - EG if var str = "wodrd sy hello";

var arr = str.split(' '); // puts str into array ["wodrd", "sy", "hello"]

var mdArr = arr.map(function(el){ return el.split('') }); // puts str into MD array [["w","o","d","r","d"],["s","y"],["h","e","l","l","o"]]



// 2. get each unique letter (remove duplicates)

function removeDuplicates(a) {

 return Array.from(new Set(a)) 

}

var letters = mdArr.map(removeDuplicates);



// 3. count # of each letter occurrences

var temp = ;

var numbers = ;



for(i=0;i < mdArr.length;i++) {



for(k=0;k < letters[i].length;k++) {temp.push(mdArr[i].filter(function(c2){return c2==letters[i][k]}).length)}



numbers.push(temp);

temp=;



}



var letterCount = letters.map((innerArr, i) => innerArr.map((letter, ii) => ({letter: letter, instances: numbers[i][ii]}))); // puts into MD array with objects:

/* returns: [

    [{letter: "w", instances: 1},{letter: "o", instances: 1},{letter: "d", instances: 2},{letter: "r", instances: 1}],

    [{letter: "s", instances: 1},{letter: "y", instances: 1}],

    [{letter: "h", instances: 1},{letter: "e", instances: 1},{letter: "l", instances: 2},{letter: "o", instances: 1}]

] */



// 4. return word from index with largest number, & first instance if matching numbers

var highestNumbers = letterCount.map((outerArr,i) => Math.max.apply(Math,outerArr.map((innerArr,ii) => innerArr.instances)));



var highestNumber = Math.max.apply(Math,highestNumbers);



var indexToReturn = highestNumbers.findIndex(function(c) { return c == highestNumber } );



return arr[indexToReturn];



}