I found a typo. On the page it says
Victory! You've done it! Nice work. Now, as we mentioned, this system isn't perfect. For instance, if the paragraph contains both "Eric" and "Eddie", we'll see this in our hits array: ['E','r','i','c','E','d','d','i','e'];
But it should be ['E','r','i','c','E','d','d','i'] . Eddie's fifth character will not get pushed in hits, because Eric is a 4 character name.