How can I return the largest number in the lengthArr array?

JavaScript
1

Tell us what’s happening:

I don’t understand what the Math.max.apply() syntax is doing

Your code so far


function findLongestWordLength(str) {
var splitArr=[];
splitArr.push(str.split(" "));

for(var i=0; i<splitArr[0].length; i++){
  var lengthArr=[];
  var myIndex=splitArr[0][i].length;
  lengthArr.push(myIndex);
  Math.max.apply(0, lengthArr);
}
return Math.max.apply(0, lengthArr);
}

console.log(findLongestWordLength("The in quick brown fox jumped over the lazy dog"));

Your browser information:

User Agent is: Mozilla/5.0 (Linux; U; Android 7.0; TECNO P701 Build/NRD90M; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/64.0.3282.137 Mobile Safari/537.36 OPR/52.1.2254.54298.

Challenge: Find the Longest Word in a String

Link to the challenge:

2

The function Math.max() takes multiple arguments in and returns the highest one.

Math.max(1,2,3,4,5); // returns 5

It will not, however, take an array in as an argument:

Math.max([1,2,3,4,5]); // return NaN

To solve this, you need to turn your array into multiple arguments. The method.apply() function takes in an array and turns it into multiple arguments, i.e.:

Math.max.apply(null, [1,2,3,4,5]) is equivalent to Math.max(1,2,3,4,5).

The first argument to the apply function supplies the this the object will see. Since that doesn’t matter unless you’re doing some object-oriented programming, passing in 0 or null is fine.

You can also use the spread operator the same way:

Math.max(...[1,2,3,4,5]); // returns 5

1 Like
3

You should read the docs as well.


4

Also keep in mind that this is one solution. If you haven’t learned the more advanced concepts described above, you can solve this problem using a loop.