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Swizec Teller - a geek with a

Experienced developers can't solve this problem

In 8 or less characters of JavaScript write an expression that evaluates to -265. You are not allowed to use "-265" as the solution or use the * character.

The other day someone asked this on IRC.

Everyone pounced on the problem and after a lot of discussion about how strange the 265 number is and whether he didn't mean 256 we decided it was impossible to solve in just eight characters.

The shortest solution I could come up with was this:

~(1 << 8) - 8;

Shifting left for eight places gives you 257, negating gives -257, then you just subtract 8 and voila, you have -265.

Except it's 9 characters long ... not a solution.

But I did learn about javascript bitwise operations, so this exercise in futility was not a total waste. Not sure what I'm going to use them for, but it can't hurt :)

So, come up with the answer yet?


Here's some solutions:

  • -1060/4 is just 7 characters
  • -256-9 is just 6 characters
  • _-530/2 _is only 6 characters as well
  • ~264 is just 4 characters (by @zidarsk8)

And so on, you get the picture. Shameful as it is, I couldn't come up with an answer at all. Never even occurred to me. I think this happens to a lot of developers who have been in the game for too long, we immediately try creating elegant solutions where simple ones will do.

If you solved this on your own, congratulations. You are better than me.

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Published on November 2nd, 2012 in Bitwise operation, Integers, JavaScript, jQuery, Languages, Programming, Uncategorized

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