My exact same solution <3

I have never heard of hasOwnProperty method before, this is so great thansk you. I have learnt sth new today

You must also aware of how in operator works because it is not only work on its parent object it is also works on object prototype chaining so let's say that property name already exists in object prototype then it will generate bug to your code

instead hasOwnProperty, i would use next exspression: if(string[i] in result);