124: JS Challenge 5

 Today's Leetcode challenge involved filtered an array using a given function. This can be done manually, first by declaring a new array to store your return value. Then you increment through your given array, and if the current value satisfies the function you push it on to the new array and eventually return it. However, it is much more elegant to use the built in Array.filter() method. Here you simply pass in your function, and the handy filter method does the rest.