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If you declare a new variable without a value, what is the "automatic" value being set?

I was almost going nuts on the last challenge!

I had everything correct but was getting "NaN" on the last function. I figured I should at least try to find the answer myself before getting it from your "solution video".

After hours of searching, and trying out different things (like parseFloat) that did not work, I finally gave up and watch your solution video.

I was befuddled when I saw that my code was exactly like yours! Well, almost.

One small change was needed.

When I declared the variable inventory_Value in my code I did like this: "var inventory_Value;"

I noticed that in the video you guys did like this: "var inventory_Value = 0;"

I tried that thinking it couldn't be that easy... But that did the trick for me!

Putting this out there if anyone else struggles with the same thing.

Thanks TTH! And good luck everyone else :)

1 Answer

Steven Parker
Steven Parker
225,652 Points

If you just declare a variable, but do not assign it, then it's value is still "undefined". Any time you do math with "undefined" the result will be "NaN".

That makes sense, thanks Steven!