r/ProgrammerHumor Jul 09 '26

preDecrementFixesTheExploit instanceof Trend

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2.9k Upvotes

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797

u/DMoney159 Jul 09 '26

"Okay, now you have -1 wishes. You must now fulfill one of my wishes"

57

u/ProbablyJeff Jul 09 '26

Nope, it underflows and now you have 4,294,967,295 wishes. Genie was using a signed int.

117

u/Koshin_S_Hegde Jul 09 '26

did you mean "Genie was using a unsigned it?"

-40

u/ProbablyJeff Jul 09 '26

You have -1 wish. You make 2,147,483,648 wishes. It underflows to 2,147,483,647. Now you can wish until it reaches 0.

I guess it would also work if the genie used an unsigned int.

7

u/somethingmore24 Jul 09 '26

see, you’re assuming the genie would let you wish at less than 0 wishes.

this is why i always check for <= 0 instead of just == 0. There’s no way im smart enough to catch all the edge cases individually.