I Can Prove That 2 + 2 = 5, And I Will!

[Universal Mind]

That's right. I can prove it. I really can. I will. You can't prove that it's not. Just try it. I can prove that it is! COME ON!!!!!

[bentrider08]

how?

[Oneironaut Zero]

[insert heavy, heavy sigh, here]

[Lord Toaster]

Then please do

[Ynot]

floating point to integer casting 2 + 2 = 5, for sufficiently large values of 2 2.4 (which is rounded down to 2) + 2.4 (which is rounded down to 2) = 4.8 (which is rounded up to 5)

[krookedking]

2+2=6 dah....

[Kaniaz]

2.4 (which is rounded down to 2) + 2.4 (which is rounded down to 2)[/b] If you casted those to ints beforehand, it wouldn't work?

[Ynot]

#include <iostream> #include <cmath> int add(float* a, float* b) { ****int c = ceil(*a + *b); *****a = (int)*a; *****b = (int)*b; ****return c; } int main() { ****float a = 2.4; ****float b = 2.4; **** ****int c = add(&a, &b); **** ****std::cout << "a + b = c" << "\n"; ****std::cout << a << " + " << b << " = " << c << "\n"; **** ****return 0; }

[Goldney]

Already knew that

[ExoByte]

[insert heavy, heavy sigh, here] [/b] I concur I get it though

[Kaniaz]

int add(float* a, float* b) { ****int c = ceil(*a + *b); *****a = (int)*a; *****b = (int)*b; ****return c; } OK...what's so special about saying that 2.4 + 2.4 rounded up to the nearest whole number is 5 (surprise)? Yes, when you cast them to integers afterwards, they become 2, because they are rounded down, but that's a loss of data - as your compiler probably says - and consequently not the same value. So when you later print the sum: std::cout << a << " + " << b << " = " << c << "\n"; You're printing out a sum different from the one add() actually carried out, i.e. a and b have changed values. I don't really get it. I suppose on dodgy calculators or something it might be a bit cooler. I think I just killed the coolness and made myself look like a pretentious bastard. Hey, what's new.

[Identity X]

Your using floats. Try turning 2 into a float in any language and you'll get 2.0 2.0 + 2.0 = 4.0 ...where is the five?

[Ynot]

it's a simple example and so, the errors blindingly obvious in a bigger program, it may be over looked imagine a big program......that calculates wages......your wages.......

[TripleX223]

lol

[Kaniaz]

Try turning 2 into a float in any language and you&#39;ll get 2.0[/b] <strike>No you won&#39;t.</strike> I read that wrong. Yes you will. in a bigger program, it may be over looked[/b] Yeah, but you&#39;d be the world&#39;s worst typecaster. C-style casts in themselves are a bit dodgy, and you&#39;d be somehow kicking the compiler in the face to stop it from warning you. imagine a big program......that calculates wages......your wages.......[/b] On the other hand, if you mean my wages are going to go up because of some rounding errors, I&#39;m all for it. Viva la float&#33;

[Ynot]

I object to the bbcode putting <?php on the box header who do you think I am &#33;&#33;&#33;

[Universal Mind]

Then please do [/b] I'm tired. I'm going to bed. I'll do it later.

[ExoByte]

HA!

[Universal Mind]

I'll explain it tomorrow. You can book it. It's a done deal. Tomorrow!

[gregash]

I'll explain it tomorrow. You can book it. It's a done deal. Tomorrow! [/b] Can I call you a liar if you don't?

[spoon]

Only if he doesn't have a really good excuse

[Neruo]

This topic reminds me of the book ' 1984' (great book). Also, only the pope can prove 2+2=5.

[Arachanox]

Once again, Neruo has something anti-Pope or Christian to say. And sure, 2 + 2 = 5 if they are both 2.4.

[Goldney]

Why is this topic still going on? What's not to get?

[Joseph_Stalin]

[/b] Yes. But see, you've just done what I can do with text, except with more work. You've haven't actually "made" 2 + 2 = 5 (which is impossible if we are allowing the 2's to represent two units and the 5 to represent five units). You've basically just coded something which will display a "picture" showing 2 + 2 = 5. Ta da: 2 + 2 = 5 Behold the magic of the characters " ". "2", "5", "+", and "=".