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[TD1]

Ah, my mistook. Me no see see, yes?

[Spehss _]

Playing around with recursion. Wrote a program that simulates a game of tower of hanoi based on a number input by the user, which determines how many discs are used.

Then made a set of data from 1 to 20 discs, finding that each iteration increases on the last iteration's total moves by 2x+1, where x is the total of moves in the last iteration. This can be made into a recursive function of f(x)=2f(x)+1.

Then wrote a program to calculate the total number of moves for any number of disks put in by the user, also using recursion and the function stated above. The output matched the data sets I have for disks 1 to 20. 1 disc takes 1 turn. 2 discs take 3 turns. 3 discs take 7 turns. etc. 20 discs take 1,048,575 turns.

The legend is that monks have a gameboard with 64 disks. When they complete the game the world ends. My calculator program calculates that a game with 64 disks will take:

Spoiler (click to show/hide)

18,446,744,073,709,551,615 correct turns.

which in words is

Spoiler (click to show/hide)

18 quintillion 446 quadrillion 744 trillion 73 billion 709 million 551 thousand 615

and assuming each turn takes 1 second then it would take

Spoiler (click to show/hide)

~5.849424174*10^11 years

to finish the game, from start to finish, assuming no mistakes are made during the game that would require a restart.

Math is kinda fun. Slightly disappointed that the wikipedia page already has all that calculated, takes the wind out of my sails a bit. Thinking about trying to run my simulator through a game of 64 discs.

[Putnam]

tower of hanoi takes 2ⁿ-1 steps to finish, where n is the number of discs in play

doing that equation ought to be MUCH faster than recursion; AFAIK, recursion for exponential functions is actually exponential time in and of itself; the fibonacci function is probably the most famous example of an exponential time exponential function

with that equation above is one step; heck, in computers, it's even easier, since the number is easily defined defined in binary:

Code: [Select]

hanoi(1)==1
hanoi(2)==11
hanoi(3)==111
hanoi(4)==1111
hanoi(5)==11111
hanoi(6)==111111

hanoi(n) is equivalent to the maximum integer that can be stored in n bits.

[hector13]

Numbers are silly.

1 one
10 ten
100 one hundred
1,000 one thousand
10,000 ten thousand
100,000 one hundred thousand
1,000,000 one million
10,000,000 ten million
100,000,000 one hundred million
1,000,000,000 should be one thousand million but no! One billion
1,000,000,000,000 should be a billion (one million million) but it's one trillion

Silliness. I blame bankers.

[Akura]

Slightly confused feelings right now. There's a cute girl at work that I sorta liked, but mostly lost interest after I heard her talking about her boyfriend. Over the past couple of weeks, I could have sworn I saw her giving me looks out of the corner of my eyes, but since I knew she had a boyfriend, I simply assumed right away I was imagining it and disregarded. No sense in tormenting myself, after all. So far, I've generally been avoiding her gaze, since making direct eye contact more than necessary is especially awkward with her.

Today I certainly did not imagine her staring at me for a good several seconds(or longer, wasn't paying attention to the passage of time) in the break room during the lunch break.

[Orange Wizard]

There's long form and short form with numbers. Long form (i.e. a million is a thousand thousands, a billion is a million millions, and a trillion is a billion billions) used to be standard, but then the Americans were all like, "nuh uh short form's better" and everyone else sort of went along with it in case you decided we were crypto-communists or something.

[Spehss _]

tower of hanoi takes 2ⁿ-1 steps to finish, where n is the number of discs in play

doing that equation ought to be MUCH faster than recursion; AFAIK, recursion for exponential functions is actually exponential time in and of itself; the fibonacci function is probably the most famous example of an exponential time exponential function

with that equation above is one step; heck, in computers, it's even easier, since the number is easily defined defined in binary:

Spoiler (click to show/hide)

Code: [Select]

hanoi(1)==1
hanoi(2)==11
hanoi(3)==111
hanoi(4)==1111
hanoi(5)==11111
hanoi(6)==111111


hanoi(n) is equivalent to the maximum integer that can be stored in n bits.

The hanoi thing was just something I tried out after reading about it in a book. After writing the example recursive program in the book (the simulator) I wanted to see if I could calculate how many turns it would take for the 64 disc game. Doing that I found the 2x+1 relation between turn totals, and found I could use that in a recursive program to calculate the turns. I guess +1 could be an inaccuracy based on my data.

I was basically playing with math and recursion and programming in my room for an hour or two without looking any of this stuff up. I had fun.

The calculator program was pretty fast.

Spoiler (click to show/hide)

Code: [Select]

psudeocode for the recursive function itself
function recur(x,count,goal)
{
count++;
if count!=goal{
y=2(x)+1;
return recur(y,count,goal);}
else return x;
}

[Cthulufaic]

There's long form and short form with numbers. Long form (i.e. a million is a thousand thousands, a billion is a million millions, and a trillion is a billion billions) used to be standard, but then the Americans were all like, "nuh uh short form's better" and everyone else sort of went along with it in case you decided we were crypto-communists or something.

scientific notation is life. 4.2*10^2 ignite it.

[inteuniso]

Slightly confused feelings right now. There's a cute girl at work that I sorta liked, but mostly lost interest after I heard her talking about her boyfriend. Over the past couple of weeks, I could have sworn I saw her giving me looks out of the corner of my eyes, but since I knew she had a boyfriend, I simply assumed right away I was imagining it and disregarded. No sense in tormenting myself, after all. So far, I've generally been avoiding her gaze, since making direct eye contact more than necessary is especially awkward with her.

Today I certainly did not imagine her staring at me for a good several seconds(or longer, wasn't paying attention to the passage of time) in the break room during the lunch break.

You're eye candy. Enjoy being eye candy, ascend into pure savagery, or put in your two weeks notice.

[Bouchart]

Today I certainly did not imagine her staring at me for a good several seconds(or longer, wasn't paying attention to the passage of time) in the break room during the lunch break.

Maybe you had spinach stuck between your teeth.

[miauw62]

I was watching GDQ because some runner I follow was running R&C:UYA, but I hadn't looked at his stream in a while.

When he got to a specific part he announced one of the hardest tricks in the game, and did fucking skrunchless.

last time i was in his stream skrunchless was basically an in-joke, a trick that saved like fifteen seconds (the WR is 33:01 right now, to give some context) and was considered to be an inconsistent gimmick forever. i did a double take.

D'you have a link of this moment, by chance?

I don't, sadly. Dunno when the videos will be up on YouTube.

I mean, the trick doesn't even look that fancy, but it was still pretty strange.

Also the runner is a professional opera singer so there was an incentive for him to sing on stream, which he did. It was great.

[Aklyon]

Considering the amount of gdq videos I've seen show up over the past week, I'd guess within a couple days of the run.

[Dutrius]

There's long form and short form with numbers. Long form (i.e. a million is a thousand thousands, a billion is a million millions, and a trillion is a billion billions) used to be standard, but then the Americans were all like, "nuh uh short form's better" and everyone else sort of went along with it in case you decided we were crypto-communists or something.

This is the one time I'll concede that the American way is better. Only because now each prefix maps neatly to a multiple of three.

Thousand = 10³
Million = 10⁶
Billion = 10⁹
etc.

[TheBiggerFish]

There's long form and short form with numbers. Long form (i.e. a million is a thousand thousands, a billion is a million millions, and a trillion is a billion billions) used to be standard, but then the Americans were all like, "nuh uh short form's better" and everyone else sort of went along with it in case you decided we were crypto-communists or something.

This is the one time I'll concede that the American way is better. Only because now each prefix maps neatly to a multiple of three.

Thousand = 10³
Million = 10⁶
Billion = 10⁹
etc.

Isn't that how SI prefixes work too?

[Akura]

You're eye candy. Enjoy being eye candy, ascend into pure savagery, or put in your two weeks notice.

Maybe you had spinach stuck between your teeth.

Sadly, I doubt either of these is true. I never eat spinach, so I'm just as likely to have a singularity lodged in my teeth. Though that would be a plausible explanation of how the spinach got there...

As for being eye candy, I'd laugh at that if doing so wouldn't hurt so very much. And there's no way in hell I'll quit because of confusion over whether or not a girl likes me or not. That, plus a great deal of discrimination, is why I left my previous job.