Slice and Splice - Can't see the problem with this code

JavaScript
1

Tell us what’s happening:
Based on the results in the FCC console, my code is returning the right values - but it’s not passing the test, and I can’t tell why. Is the FCC not displaying accurate results?

slice-splicej
slice-splicej1988×1220 377 KB

Your code so far


function frankenSplice(arr1, arr2, n) {
  // It's alive. It's alive!
  let first = arr2.slice(0,n);
  let second = arr2.slice(n);
   
  for (var i = 0; i < arr1.length; i++) {
    var element = arr1.slice(i,i + 1);
    first.splice(first.length,0,element); 
  }  
  first.splice(first.length,0,second);
  return first; 
} 

console.log(frankenSplice([1, 2, 3], [4, 5], 1));
console.log(frankenSplice([1, 2], ["a", "b"], 1));
console.log(frankenSplice(["claw", "tentacle"], ["head", "shoulders", "knees", "toes"], 2));

Your browser information:

User Agent is: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:62.0) Gecko/20100101 Firefox/62.0.

2

Why don’t you check what your code does using this tool?

http://pythontutor.com/javascript.html

1 Like
3

You are creating a multi-dimensional array. You should have a flat array. Because of the way the arrrays are printed in the browser console, this isn’t obvious. You can see it by wrapping your frankenSplice call in JSON.stringify() or by using a REPL environment like the one linked below.

1 Like
4

Thanks! I’ll remember this one.

5

thanks! - now to fix. hmmm…