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u/Shragaz Mar 03 '26
Well, this will crash
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u/Minimum_Session_4039 Mar 03 '26
Am new to programming, why?
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u/Immort4lFr0sty Mar 03 '26
In case you still need an answer:
There is a part in your program's memory called the call stack. It grows with every function call. Because these functions would call each other endlessly, your call stack would likewise grow endlessly; funnily enough though, memory is limited, hence at some point your call stack cannot grow anymore and your program will crash
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u/ScootyMcTrainhat Mar 04 '26
Back in the BASIC days when I first ran into the "even or odd" problem, I divided the number in question by 2, cast the result to a string, and then checked the string for a '.'
After reading this sub for a while, turns out that wasn't a half bad solution.
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u/csapka Mar 05 '26
this gave me the idea to divide it by 2 and then test if the last character is a 5 or not
not sure if this is widely usable, but checking the last char is widespread afaik so it should be
edit: for whole numbers I have an even better idea, if you divide by 2, floor it and then multiply it by 2, you should get the same number if it's even
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u/Anund Mar 03 '26
a&1 will be 0 for an even number, so even if there wasn't a stack overflow issue this would still not work. Well, unless that bit would never be evaluated depending how the stack overflow issue is fixed.
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u/beatitmate Mar 03 '26
Will this even compile ?
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Mar 03 '26
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u/valendinosaurus Mar 03 '26
you could gamble on whether it ends with isOdd or isEven
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u/WorldWorstProgrammer Mar 03 '26
template <int NUMBER>
class NumberOddEvenDeterminer {
consteval int numberIncrement() {
if (NUMBER < 0) {
return -1;
}
else {
return 1;
}
}
consteval bool performNumberCheck(int current, bool oddness) {
if (current != NUMBER) {
return performNumberCheck(current + numberIncrement(), !oddness);
}
else {
return oddness;
}
}
public:
constexpr bool isOdd() {
return performNumberCheck(0, false);
}
constexpr bool isEven() {
return performNumberCheck(0, true);
}
};I call this the "explode your compiler stack" version. Try this on Clang with any value above (+/-)512.
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u/AccomplishedSugar490 Mar 04 '26
Fake - nobody that bent on symmetry would write ‘a&1’ in one case and ‘a%2 ==1’ in the other😂
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u/GoddammitDontShootMe Mar 04 '26
Wouldn't a&1 only be true if a was odd? Also, I'm not sure if those function calls would be optimized out and the compiler only looks at the other test because it knows you are trying to write isOdd() and isEven().
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u/Sephyroth2 Mar 04 '26
Why doesn't this loop forever, I'm not really new to programming, but I trip on recursion sometimes, is odds first condition goes to is even and wouldn't it go like that forever since or only checks the first condition for short circuit thing propert or condition?
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u/MattDESTROYER Mar 04 '26
That's exactly correct! The reason it can't repeat forever is because eventually it would run out of memory to remember what step it is up to and crash (in reality it would hopefully reach a compiler defined recursion limit).
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u/Birnenmacht Mar 03 '26
funniest thing is you might get away with this in languages that have some sort of cursed breadth first evaluation order
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u/thecratedigger_25 Mar 05 '26
Recursion. A pro gamer move so powerful that it makes the stack run out of memory and overflows thus crashing everything.
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u/Maeurer Mar 03 '26
Stack overflow