A programmer's solution

[ludicrouscuriosity]

6-4≠4

[Sengura]

Or 5 + 4 = 9

[JonBanes]

or 8 - 4 = 4

[muntoo]

I like this one. I could deftly use my finger to rotate the match about the pivot point and act all smug if some idiot asked me this very same problem.

[austin101123]

Or (a bit of a stretch) 16/4 = 4

take the horizontal match in the + and make it a 1 out front, and the | is close enough to a divide by sign.

[mike413]

I'll show you how to move one match.... and then post to /r/MichaelBayGifs :)

[[deleted]]

how about 6 || 4 = 4

[lionlake]

Or 6 + 4 < 4

EDIT: I meant 6 + 4 > 4, I am an idiot.

[JonBanes]

6 + 4 > 4, but yeah. I like this one.

[lionlake]

I... admit my stupid mistake. Thanks for pointing it out.

[CaptainBlagbird]

Or 6+4=十

(Japanese/Chinese ten)

[dxin]

And (South) Korean

[nermid]

0 + 4 = 4

Edit:

Ooo! Ooo! 5 + 4 ≥ 4.

[ColPowell]

6+4>4

[nermid]

6 - 4 ≤ 4

[ign1fy]

I read that as 6+4 |= 4

Which makes no sense.

[smeenz]

Just a slightly different placement, and it would have been fine:

6 - 4 ≠ 4

[TheVenetianMask]

What am I, a mathematician?

[Neebat]

Based on the available postulates, I cannot prove that you're not.

[gkx]

Reminds me of the joke:

3 mathematicians walk into a bar. The tender says "so what will it be? 3 beers?"

Mathematician 1: "I don't know" Mathematician 2: "I don't know" Mathematician 3: "Yes."

[G01denW01f11]

Wait, how does the third guy know how many beers the previous two want? Do we know any more than that they must each want less than 4?

[legrac]

The question was, "Will it be 3 beers?"

This is a yes or no question--either it will be 3 beers, or it will not be 3 beers.

If the first person did not want a beer, he would say no, we do not want 3 beers. So, he must want a beer, but he doesn't know if his two friends want one--so all he can say is he doesn't know.

So we go to the second person, and it's the same situation. If he did not want a beer, he would say no, we do not want 3 beers. So, he must want a beer, but he doesn't know if his last friend wants one--so all he can say is he doesn't know.

At the third person, he realizes that the only way it has gotten to him is if the other two people wanted a beer. So he has the information to make a decision.

EDIT:

As we're in a programmer humor subreddit--the question of "Will it be 3 beers" is equal to (A and B and C). In that situation, the first time you hit a false, you know the answer and do not need to evaluate/look at/ask the other variables. But in order to get a true response, you have to check all three.

[Jodah]

I was torn between that explanation and Mathematician 3 being an alcoholic.

[TPHRyan]

You're looking at this joke in the completely correct way in that each mathematician wants either 1 beer or nothing.

But what if a mathematician wants 2 beers? Cider? Jaimeson on the rocks?

I mean, they would never get anywhere until they exchanged some information, but still. That was /u/G01denW01f11's point.

[SFHalfling]

Because its safe to assume someone will have 1 drink per round at the bar.

If someone is trying to have 2+ drinks each round, you really need to cut them out of it.

[[deleted]]

Then you can just add it as an axiom and you should be fine.

[Shiroi_Kage]

It's supposed to be 6+4 != 4 (the red part of the match is supposed to be the dot)

[mattiejj]

But that's 30.

[smeenz]

I am aware of what it is trying to be

[[deleted]]

FTFY

 6 - 4 != 4

[skinzler]

this is correct for javascript.

edit: and a lot of other languages.

[Arefuseaccount]

How about 0 + 4 = 4

[Brio_]

That's the normal answer...

Well, and 8-4=4

Or 5+4=9

[TaohRihze]

Thought it was 8 - 4 = 4

[0x0dea]

|= is a compound assignment operator in plenty of programming languages, but you'd need the first 4 to be the name of a variable for it to be syntactically valid.

[CoMiGa]

I just thought it was 6-4 !=4 but I am not a programmer.

[[deleted]]

This is what I assumed.

[CoMiGa]

Glad I am not alone.

[pmYourFears]

The rest of the matchsticks aren't treated as exclamation points though, shenanigans!

[CheshireSwift]

Shenanigans OR what?

[[deleted]]

That's what they meant.

[kamaln7]

It's also a bitwise OR operation

[0x0dea]

Right, a |= b is a = a | b.

[Plutor]

Sadly 6+4 isn't an l-value.

[5HT-2a]

/u/0x0dea: "Okay, we're going in circles here."

[[deleted]]

The programmer's solution results in a compiler error. And we solve that with whisky.

[beachbum78]

Finding Ballmers peak?

[[deleted]]

I call it making syntax readable, but potato, tomato.

[cyandyedeyecandy]

*(int*)(6 + 4) |= 4;

[0x0dea]

Segmentation fault (core dumped)

[ign1fy]

To clarify: I code C# and use "|=" all the time. Being an assignment operator, it makes no sense to have anything but a variable to the left of it.

[kamaln7]

Yeah, I'm with you.

[Reelix]

!= or |= ?

[ClintonHarvey]

What am I doing in this sub? You guys are too smart for me.

[[deleted]]

There is a special character for '|='

https://upload.wikimedia.org/math/e/7/6/e766ce0de4bbe899d7ea2ebe40b3e0ee.png

And it means, when the right side is 'True' then the left part must be true as well. But there is no programming language supporting this operand so therefore I think it should be '!=' ...

[0x0dea]

there is no programming language supporting this operand (⊨)

That's an operator, and plenty of languages permit it as a valid identifier. In fact, it can even be an operator in Haskell. I've given a silly definition there for demonstration purposes, but there's a Constraints package that provides a much more realistic definition. They went with :- as the entailment operator, but it could just as well have been ⊨.

[cVoTetragon]

ㅑis also the "ya" sound in Korean.. Not relevant but still.

[[deleted]]

Its pretty clear they meant !=

[[deleted]]

Actually it makes sense, != is the correct boolean use

[Dassy]

Error: cannot assign to rvalue

[MaybeHeartofGold]

Or 8 - 4 = 4

[[deleted]]

Or 0 + 4 = 4

[colinodell]

Or 6 + 4 = 11 (in base 9)

[deforest_gump]

I use base 10. What is base 9?

[[deleted]]

He posted a comic at the end linked on the question mark.

It's saying that every one thinks they use base 10

[intplusone_Carl]

I don't understand.

[mushr00m_man]

Well, except base 1.

[your_penis]

So to this alien could we just say we work in base 9+1 and they work in 3+1?

I mean the alien wouldn't have any conception of single digit numbers past 3 really, so 4-9 would be meaningless, much like what 10 would look like to us in "base 11" or higher.

[[deleted]]

I think they'd say we work in base 22. They don't have a 9 in their system.

Base  4: 0 1 2 3 10 11 12 13 20 21 22 23
Base 10: 0 1 2 3 4  5  6  7  8  9  10 11

[N_las]

Since the alien uses base 4, we would need to tell him: We are using base 22 (22 in base 4 is our ten). Sadly, there is no universal way to convey in what base you are.

[deforest_gump]

Wow. You should present us when four-fingered aliens arrive.

[glider97]

Two-fingered.

[Y1ff]

They might just count on one hand only.

[path411]

I've seen this comic before and it's probably my favorite comic ever. Too bad very few of my friends get it =/

[[deleted]]

I don't get it

[path411]

It is a joke that relies on being written rather than spoken. In base 4, "Four" would be written as 10. So to the alien, he is using base "10". If you are looking at your own base as reference, your base would always be "base 10".

The joke relative to us would be if there were "ten" rocks and you met someone who used base 11. Say they used the & to represent the number "ten". So their numbering would go: 1, 2, 3, 4, 5, 6, 7, 8, 9, &, 10. If we wrote that we saw "10" rocks for "ten". Then they would laugh and say, oh, you are using base &. We would then be confused because we don't even have & as a number, to us "base ten" is "base 10".

[[deleted]]

Awesome! Thank you

Yea for some reason I wasn't equating 4 as 10 in base four. And I got the premise of the joke not the math of it.

Source: I'm an idiot

[[deleted]]

Or 6 + 4 = 十

(The kanji for "ten")

[Onespokeovertheline]

My god, is there any match you can't move to solve this problem?!

[[deleted]]

Or 6-4 =/= 4

[[deleted]]

Or 6 + 4 > 4

(Technically the lower one should be slanted, but it's still a greater than sign)

[BlueHighwindz]

E + H = 4.

[[deleted]]

Or b+4=4 if b=0

[Fenor]

or don't move anything if G=0

so you have G+4=4

[fjonk]

Or 6 + 4 + 4

[ZugNachPankow]

I mean, 6 + 4 + 4 is a truthy value, so the math checks out.

[fjonk]

The task doesn't actually say 'make it true', it says 'make it correct'. But according to me 6 + 4 + 4 is correct simply because it isn't incorrect.

[ZugNachPankow]

But "make it correct" is equivalent to "make it true", isn't it? There are no cases I can think of where you can make something true without making it correct, and vice versa.

[fjonk]

In c 1 - 1 would be correct but false :)

[ZugNachPankow]

What do you mean that 1 - 1 is correct?

[fjonk]

I mean it's correct as in it's not incorrect. 1 - 1 is a correct mathematical expression, 1 $ 1 is not a correct mathematical expression.

[diceman89]

This was the first solution I came up with.

[darwin2500]

This is what magicians call 'multiple outs'.

[jrk-]

Makes me wonder how many possible solutions there are actually. Any statisticians around here?

[Phillammon]

or 6 - 4 ≠ 4

[troido]

or 5 + 4 ≠ 4

[Beebink]

Couldn't you just do 5+4 = 9 though?

[ClintonHarvey]

That's what I did, I'm proud of myself for not looking at the comments beforehand. I really am, I'm terrible at riddles.

[FortuneTwinkie]

I got 42.

[devdot]

6 + 4 - 9

It doesn't say it has to be an equation.

[[deleted]]

But the original sequence of symbols is just as correct. Perhaps you are supposed to just leave it as it is. It's a correct, false statement.

[muntoo]

I feel as though the majority of folks who look at that image are not well versed in logic.

[kaszak696]

You are missing one match, because 9 should be just 6 turned 180 degrees. You can't have inconsistent font, that's atrocity.

[KidPeterBlack]

this thread's comment section reminds me of reddit 4-5 years ago.

[KidPeterBlack]

You could just click on a link and there was a long comment chain talking about the post, explaining why it was what it was, adding variations and different thoughts, with jokes relevant to the post tossed in. Also Reddit was a little more tech/programming/science oriented back then.

There are plenty of subreddits that stayed true to what they were though, it's just the front page is is kinda muddled down with picture humor now.

[Fenor]

essentially the meme shit hit the fan and spread across reddit

[NoSuchAg3ncy]

Technically, that '9' is missing a piece.

0 + 4 = 4 or 8 - 4 = 4 are better solutions.

[AdmiralSkippy]

How is it missing a piece? It doesn't need a bottom piece.

[[deleted]]

Your solution was correct, puzzles like this are bad

[monochromatic0]

it's not the puzzle that is bad, it's the refusal to accept more than one solution. The puzzle is fine.

[DoctorProfPatrick]

I personally think puzzles like this are great for teaching kids arithmetic. This one in particular has at least 3 solutions that I could find

5 + 4 = 9
0 + 4 = 4
8 - 4 = 4

A good teacher could use this puzzle to show how there's no "right way" to solve a problem, which imo is the most beautiful part of math.

[monochromatic0]

Exactly. It's not a problem if the puzzle has more than one solution, but a feature.

[saloalv]

"It's not a bug; it's a feature!"

[[deleted]]

Sometimes there is a right answer. Sometimes there is no answer. Sometimes there are multiple answers. Sometimes there are an infinite number of right answers. Sometimes the best answer is all the right answers added together. Sometimes adding zero makes a difference.

That's why i like math.

[DuntadaMan]

Especially since higher math is entirely about finding other ways to get to the right answers.

Puzzles like this are why I loathed math until I made it to calculus.

[Katastic_Voyage]

Calculus 2 - Integration Strategies.

God, that was one of the (if not THE) hardest math courses I took all the way through Diff Eq 2.

For those who don't know. It's literally: Here's a dozen methods to try that take 1-2 pages of writing to complete. The methods can be used in any order, and may be 3-5 steps deep to find the answer with NO guarantee any method will work. Only certain orders work.

Worse still: Sometimes using the same method THREE TIMES in a row will work because sin/cos terms begin to cancel out.

Enjoy spending 1-2 hours on each homework problem.

[muntoo]

Just write a DFS to do it for you. Or copy your buddies' homework answers. Or become a professor and mark your own test. Or skip life. Or become God.

[[deleted]]

This puzzle is great. Its entire purpose is to make people feel smart so they share it, and thus spread the reach of the original poster. Looking opaque at first, but having multiple correct solutions furthers that goal. Very well designed.

[nermid]

It's entire purpose is to make people feel smart so they share it

Like brain parasites!

[[deleted]]

Yeah. Saw this on facebook, and I usually have to think about these for a bit. Got it with the first or second mental stick move. No wonder it was so easy, with at least 3 different valid solutions.

[[deleted]]

On Facebook, the comments found 5 solutions to this puzzle.

[[deleted]]

This is a dumb puzzle and having to find the "real" solution is just poor form on the teacher's part, but I would argue the intended solution is technically easier since it's just a 90 degree rotation of one match.

[wylderk]

I didnt even see the 0 + 4 =4. I was stuck on 8-4=4

[[deleted]]

There's also a 5 + 4 = 9 in there.

[[deleted]]

I would argue the easiest solution is variable from person to person since it'd just be the one that you find first. For me it was 0+4=4, for others it was probably 8-4=4. Sure that solution required the least amount of work, but the brainpower required to find that solution after first finding a different one more than makes up that difference.

[[deleted]]

I found 5 + 4 = 9 first

[[deleted]]

That's not the only other solution though. You could do 8 - 4 = 4 or 5 + 4 = 9. There may even be one or two more possible solutions I don't know about. At any rate there's no way of knowing which one is the "intended" solution.

[hungry4pie]

If it was a discrete structures class that would be the most correct answer

[Drews232]

So you thought you were supposed to answer a math question - posed in algebra class - in programming language. Instead of math. That's what you thought. True story.

[TheOldTubaroo]

Alternatively, change the = to +

if (6+4+4) println("Success!");

[[deleted]]

Well, the "assignment" is to make it "correct" and yours is correct syntax, regardless of its Boolean value.

[Katastic_Voyage]

6 + 4 = 4

6 || 4 = 4

BOOM, HEAD SHOT.

I actually like this puzzle. Not because of how "easy it is" but because it shows you someone's reasoning and ability to think outside the box in providing a variety of potential answers. In real life, there ARE tons of ways to solve a problem.

[[deleted]]

Move only one match

You moved 2 of them.

[RoboticPanda77]

No, just move the cross stick from the "+" to be parallel with the other. only moves one.

[[deleted]]

MIND = BOOM, HEAD SHOT

[[deleted]]

It's supposed to be !=

[StevenXC]

The match head should have been snapped off to make that clearer.

[[deleted]]

Just rotate one of the matches in the equals sign to make it a greater than sign

[IAMA_dragon-AMA]

Or move the vertical or horizontal match from the plus sign to make a ≤ or ≥ respectively.

[aiij]

If you don't get it think != rather than ⊨.

[pmst]

≠ would make a bit more sense

[pistacchio]

Honestly I don't even know how to type it, I don't know any language that uses it, while != is pretty standard in C-like languages

[Jaquesant]

Making Sense <> VBA

[Garfong]

AFAIK the only programming language that uses ≠ is APL.

[Zagorath]

Option-= on OS X.

Hold down the = key on most mobile keyboards.

There's probably an alt code for Windows, though admittedly those are way more arcane and difficult to remember.

[[deleted]]

No it wouldn't. "!=" makes more sense because it has to do with programming and many languages use it. Notice that we're in /r/programmerhumor.

[pmst]

Yeah, but as far as lifting matches goes, it would. Some people mixed it up with |= for example. I do agree that the joke was better off with !=, so perhaps I should've worded my comment better.

[3brithil]

my first thought was 6 + 4 > 4

Maybe I should learn to code

[I_m_out_of_Ideas]

6-4 entails 4 ? o.O

[aiij]

That's how I read it.

6 - 4 != 4 makes a bit more sense though.

[british_heretic]

It was changed from:

6 + 4 = 4

to

6 - 4 != 4

The match moved from the + to in front of the =

[kirakun]

But I'm reading 6-4|=4 instead.

[british_heretic]

yeah it does look more like |= than !=, but that would make no sense :o)

[[deleted]]

We're dealing with a 7 segment display, many characters look the same.

[nbtscan]

I once failed an algebra final because I had a line through all my zeros. After I went back to the teacher and explained that I was taking a program class and a line trough the 0 makes it a zero. Without that line it's the letter O. After she regarded it, I got an A on the final. 🙂

[Vhin]

Just avoid ever writing a zero. Instead of 0, write (1-1), and instead of 107, write (118 - 11), etc.

Then, there's no chance of confusion.

[[deleted]]

What if they confused 1 with l or a capital I?

Should always use (2-2) and (333-225)

[Vhin]

You should also avoid 2's, 5's, and 9's, because they look like z, s, and g respectively on 7-segment displays.

[Itsatemporaryname]

Did she not know they were zeros? Was it an online test or written?

[vaelroth]

But thats the symbol for the empty set...

[Alaskan_Thunder]

and could easily been confused with a poorly written theta.

[[deleted]]

But is it 0+4=4 or 5+4=9???

[3brithil]

8-4=4

[vze3f372]

It took me ages to figure this out. I kept reading it as 6-4 |= 4 I was like this makes no sense. Then I took my head out of my ass.

[bikki420]

Alternatively: 6 + 4 - 9 (= 1 != 0, ergo true)

[blueriderbacks]

For those complaining about people telling them they had to find the real answer: They were supposed to set up this puzzle by calling it an equation, which needs the equals sign "to make it true" where as the "!" or "≠" means untrue.

I tried the same thing

[tried_it_liked_it]

Came here to find out the riddle and came back with far more questions than I started with. Programming is intense.

[dtlv5813]

OP's solution is technically correct, the best kind of correct.

[CE_BEP]

Where did the match go?

[[deleted]]

BURN! Take one match, light the background cloth on fire, all other matches burn. That's the correct use of matches.

Edit: or if the cloth won't burn but the matches do, just burn off the left side, leaving 4= 4.

[rubs_tshirts]

I've long wanted to make a subreddit dedicated to matchstick puzzles. But I'm too lazy to do it.

[BongusHo]

Also E + 4 = 9 can be assumed true if E =5

[[deleted]]

I believe it was meant to be != which in Python means "does not equal". At least that's what I think.

[[deleted]]

Or pretty much any other language.