My python one-liner scramble generator

[qqwref]

Yep, I tried using & but that broke it. I think it's because to get x|y=0 you need each bit of x and y to be 0 (i.e. x=y=0), whereas & does not work out as nicely.

 

[PatrickJameson]

Ahh, I understand what's going on now with bitwise operations. At least for OR. When I did it I had no idea what was going to happen, I was just hoping for the best

 

[cuBerBruce]

A GAP random-state scramble generator(169 characters, only the last 37 characters needed for additional scrambles - the text in red is one-time initialization code):

Spoiler

G:=Group(U,D,L,R,F,B);;P:=FreeGroup("U","D","L","R","F","B");;h:=GroupHomomorphismByImages(P,G,GeneratorsOfGroup(P),[noparse][U,D,L,R,F,B]);;[/noparse]
PreImagesRepresentative(h,Random(G));

OK, I cheated a bit. The output doesn't look exactly what it should look like. I also omitted initialization of globals U,D,L,R,F, and B (which also only needs to be done once, of course). (Note: The "forum" put in a couple of unwanted space characters, should be fairly obvious.)

 

[qqwref]

OK, I cheated a bit.

I'd say you cheated a lot :| The permutations U,F,R,D,L,B take a significant amount of space to define. If you don't count variable initializations then I claim the following JS code:

for(;j<k;c+b-5|c-m&&b-m?w(x[j++,c=b,b=m]+y[s()]+z):0)m=t()

 

[guzman]

Recap 2:

Recap 2:

perl: 98 (edit, sub100!!) (Patrick, Johannes91, Stefan, qqwref)

map{$m=0|rand 6until$c+$b-5|$c-$m&&$m-$b;$c=$b;print" ".(U,R,F,B,L,D)[$b=$m].qw(' 2)[rand 3]}1..25

C++: 103 (111 with main(){} ) (edit) (keemy, Marcell, guzman, Portponky)

for(int c=0,b=6,j=25,m;j;(m=rand()%6)-c|c+b-5&&b-m&&cout<<"URFBLD"[j--,c=b,b=m]<<" 2'"[rand()%3]<<" ");

perl: 111 (Stefan)

$_.=chr rand 99,/[^URFBLD]|(.)\1|LRL|RLR|UDU|DUD|FBF|BFB/&&chop until/.{25}/;s/./" $&".qw(' 2)[rand 3]/ge;print

javascript: 114 (qqwref, Devin, guzman, Johannes91, Patrick, Stefan)

r=Math.random;for(c=b=j=0;j<25;c+b-5|c-m&&b-m?document.write("URFBLD"[j++,c=b,b=m]+" 2'"[0|r()*3]+" "):0)m=0|r()*6

Ruby: 115 (joey)

p (x=y=0..25).map{z=x;x=(w=[%(UD),%(FB),%(RL)][rand 3])[rand 2] until x!=y||z!=x&&w[y];(y=x)+"2'"[rand 3].to_s}*" "

perl: 115 (Patrick, Stefan)

do{$_=join'',map{(U,R,F,B,L,D)[rand 6]}1..25}while/(.)\1|LRL|RLR|UDU|DUD|FBF|BFB/;print" $_".qw(' 2)[rand 3]for/./g

php: 116 (Marcell, guzman)

for($i=$b=$c=0;$i<25;$M="URFBLD 2'")if(($b-$m=rand()%6)&($c+$b-5|$c-$m))echo$M[$b=$m+0*$i++*$c=$b].$M[rand(6,8)].' '

python: 149 (masterofthebass)

from random import randint as r;c=b=0
for i in range(25):
 m=r(0,5)
 while (c+b-4 or c==m)and m==b:m=r(0,5)
 print "URFBLD"[m]+" '2"[r(0,2)],;c=b;b=m

mathematica: 166 (Lucas)

StringJoin[ToString[#]<>(c=RandomChoice)[{" ","' ","2 "}]&/@(Flatten[RandomSample[#,Ceiling[Random[]*5/4]]&/@c[{{U,R},{F,B},{L,D}},25]]//.{a___,b_,b_,c___}:>{a,b,c})]

 

[guzman]

I'd say you cheated a lot :| The permutations U,F,R,D,L,B take a significant amount of space to define. If you don't count variable initializations then I claim the following JS code:

for(;j<k;c+b-5|c-m&&b-m?w(x[j++,c=b,b=m]+y[s()]+z):0)m=t()

Or, just

p()

where the initialization of p is omitted.

 

[Portponky]

The c++ algorithm can't produce a U turn on its first move. Initialize b to something like 6 to allow this.

 

[guzman]

The c++ algorithm can't produce a U turn on its first move. Initialize b to something like 6 to allow this.

You're right, thanks, I'll update it.

Edit: same goes for javascript, php, python.
I think we should set b=c=j=6 and j1.

 

[PatrickJameson]

Recap 2:
(the 98 chars perl code was wrong, right?)

Nope, the 98 perl works . There was just some doubt for a bit.(aha, bit, get it? because the doubt was over bitwise operations. I'm hilarious).

 

[guzman]

Nice!!
ok, edited.

 

[Stefan]

I think the 98er can't start with U turns, either.

guzman: It's python, not pyton.

 

[guzman]

Sorry, edited.

I also added authors,
hope I didn't forget anyone.

Edit:

I think the 98er can't start with U turns, either.

Let's say we print 27 moves and it's up to the user to skip the first two moves ...

 

[joey]

That 115 char ruby one is all mine

 

[guzman]

That 115 char ruby one is all mine

Edited

Edit: or were you joking?

 

[Marcell]

Damn, the timezones...
Anyway, it's really impressive what you did to that Perl code. And congrats to the sub100.

If only I could understand what the regex one does...

 

[Portponky]

for(int j=0;j<25;j++)
for(int j=25;j;j--)

2 character saving for c++

for(int c=0,b=6,j=25,m;j;(m=rand()%6)-c|c+b-5&&b-m&&cout<<"URFBLD"[j--,c=b,b=m]<<" 2'"[rand()%3]<<" ");

 

[guzman]

for(int j=0;j<25;j++)
for(int j=25;j;j--)

Yeah, true. Nice one.

 

[Marcell]

for(int j=0;j<25;j++)
for(int j=25;j;j--)

2 character saving for c++

Neat!

 

[Kynit]

This thread is actually starting to scare me a little. 98 characters to make a legitimate scramble? Incredible.

 

[Stefan]

98 characters to make a legitimate scramble? Incredible.

And so far, not achieved.

Saving 1 by not wasting the loop body:
for(int c=0,b=6,j=25,m;j;m-c|c+b-5&&b-m&&cout<<"URFBLD"[j--,c=b,b=m]<<" 2'"[rand()%3]<<" ")m=rand()%6;

I guess another could be saved by making the variables global so we don't need the =0, but then we really ought to include and count "main...".