Code Golf: Playing TetrisConsider the following tetrominoes and empty playing field:
0123456789
I O Z T L S J [ ]
[ ]
# ## ## ### # ## # [ ]
# ## ## # # ## # [ ]
# ## ## [ ]
# [ ]
[==========]
The dimensions of the playing field are fixed. The numbers at the top are just here to indicate the column number (also see input).
1. You are given a specific playing field (based on the above) which can already be filled partly with tetrominoes (this can be in a separate file or provided via stdin).
Sample input:
[ ] [ ] [ ] [ ] [ # # #] [ ## ######] [==========]
2. You are given a string which describes (separated by spaces) which tetromino to insert (and drop down) at which column. Tetrominoes don't need to be rotated. Input can be read from stdin.
Sample input:
T2 Z6 I0 T7
You can assume input is 'well-formed' (or produce undefined behaviour when it's not).
Render the resulting field ('full' lines must disappear) and print the score count (every dropped line accounts for 10 points).
Sample output based on the sample input above:
[ ] [ ] [ ] [# ###] [# ### ] [##### ####] [==========] 10
Shortest solution (by code character count). Usage examples are nice. Have fun golfing!
Edit: added a bounty of +500 reputation to draw some more attention to the nice efforts the answerers already made (and possibly some new solutions to this question)...
ACCEPTED]
Newlines are not necessary. Output is in standard output, although some errors are present in stderr.
\10 should be replaced by the corresponding ASCII character for the program to be 181 characters.
{):X!-{2B{" #"=}%X" ":f*+-1%}%:P;:>.{\!:F;>P{\(@{3&\(@.2$&F|:F;|}%\+}%\+F![f]P+:P
;}do;{"= "&},.,7^.R+:R;[>0="#"/f*]*\+}0"R@1(XBc_""~\10"{base}:B/3/~4*"nIOZTLSJR "
";:"*~;n%)n*~ 10R*+n*
Sample I/O:
$ cat inp
[ ]
[ ]
[ ]
[ ]
[ # # #]
[ ## ######]
[==========]
T2 Z6 I0 T7
$ cat inp|golfscript tetris.gs 2>/dev/null
[ ]
[ ]
[ ]
[# ###]
[# ### ]
[##### ####]
[==========]
10
Tetromino compression:
Pieces are stored as three base 8 digits. This is a simple binary representation, e.g.T=[7,2,0], S=[6,3,0], J=[2,2,3]. [1] is used for the I piece in compression, but this is explicitly set to [1,1,1,1] later (i.e. the 4* in the code). All of these arrays are concatenated into a single array, which is converted into an integer, and then a string (base 126 to minimize non-printable characters, length, and not encounter utf8). This string is very short: "R@1(XBc_".
Decompression is then straightforward. We first do a base 126 conversion followed by a base 8 conversion ("~\10"{base}/, i.e. iterate through "~\10" and do a base conversion for each element). The resulting array is split into groups of 3, the array for I is fixed (3/~4*). We then convert each element to base 2 and (after removing zeros) replace each binary digit with the character of that index in the string " #" (2base{" #"=}%...-1% - note that we need to reverse the array otherwise 2 would become "# " instead of " #").
Board/piece format, dropping pieces
The board is simply an array of strings, one for each line. No work is initially done on this, so we can generate it with n/( on the input. Pieces are also arrays of strings, padded with spaces to the left for their X position, but without trailing spaces. Pieces are dropped by prepending to the array, and continuously testing whether there is a collision.
Collision testing is done by iterating through all characters in the piece, and comparing against the character of the same position on the board. We want to regard #+= and #+# as collisions, so we test whether ((piecechar&3)&boardchar) is nonzero. While doing this iteration, we also update (a copy of) the board with ((piecechar&3)|boardchar), which correctly sets the value for pairs #+, +#, +[. We use this updated board if there is a collision after moving the piece down another row.
Removing filled rows is quite simple. We remove all rows for which "= "& return false. A filled row will have neither = or , so the conjunction will be a blank string, which equates to false. Then we count the number of rows that have been removed, add the count to the score and prepend that many "[ ... ]"s. We generate this compactly by taking the first row of the grid and replacing # with .
Bonus
Since we compute what the board would look like in each position of the piece as it falls, we can keep these on the stack instead of deleting them! For a total of three characters more, we can output all these positions (or two characters if we have the board states single spaced).
{):X!-{2B{" #"=}%X" ":f*+-1%}%:P;:>.{>[f]P+:P(!:F;{\(@{3&\(@.2$&F|:F;|}%\+}%\+F!}
do;{"= "&},.,7^.R+:R;[>0="#"/f*]*\+}0"R@1(XBc_""~\10"{base}:B/3/~4*"nIOZTLSJR "
";:"*~;n%)n*~ ]{n*n.}/10R*
(Needs Perl 5.10 for the defined-or // operator).
Takes all input from stdin. Still needs some serious golfing.
Note that ^Q represents ASCII 17 (DC1/XON), ^C represents ASCII 3 and ^@ represents ASCII 0 (NUL).
while(<>){push@A,[split//]if/]/;while(/\w/g){for$i(0..6){for($f=0,$j=4;$j--;){$c=0;map{if($_){$i--,$f=$j=3,redo if$A[$k=$i+$j][$C=$c+$'+1]ne$";$A[$k][$C]="#"if$f}$c++}split//,unpack"b*",chr vec"3^@'^@c^@^Q^C6^@\"^C^Q^Q",index(OTZLSJI,$&)*4+$j,4;$s+=10,@A[0..$k]=@A[$k,0..$k-1],map{s/#/ /}@{$A[0]},$i++if 9<grep/#/,@{$A[$k]}}last if$f}}}print+(map@$_,@A),$s//0,$/
Commented version:
while(<>){
# store the playfield as an AoA of chars
push@A,[split//]if/]/;
# while we're getting pieces
while(/\w/g){
# for each line of playfield
for$i(0..6){
# for each line of current piece
for($f=0,$j=4;$j--;){
# for each column of current piece
$c=0;
map{
if($_){
# if there's a collision, restart loop over piece lines
# with a mark set and playfield line decremented
$i--,$f=$j=3,redo if$A[$k=$i+$j][$C=$c+$'+1]ne$";
# if we already found a collision, draw piece
$A[$k][$C]="#"if$f
}
$c++
# pieces are stored as a bit vector, 16 bits (4x4) per piece,
# expand into array of 1's and 0's
}split//,unpack"b*",chr vec"3^@'^@c^@^Q^C6^@\"^C^Q^Q",index(OTZLSJI,$&)*4+$j,4;
# if this playfield line is full, remove it. Done by array slicing
# and substituting all "#"'s in line 0 with " "'s
$s+=10,@A[0..$k]=@A[$k,0..$k-1],map{s/#/ /}@{$A[0]},$i++if 9<grep/#/,@{$A[$k]}
}
# if we found a collision, stop iterating over the playfield and get next piece from input
last if$f
}
}
}
# print everything
print+(map@$_,@A),$s//0,$/
Edit 1: some serious golfing, fix output bug.
Edit 2: some inlining, merged two loops into one for a net saving of (drum roll...) 3 chars, misc golfing.
Edit 3: some common subexpression elimination, a little constant merging and tweaked a regex.
Edit 4: changed representation of tetrominoes into a packed bit vector, misc golfing.
Edit 5: more direct translation from tetromino letter to array index, use non-printable characters, misc golfing.
Edit 6: fixed bug cleaning top line, introduced in r3 (edit 2), spotted by Nakilon. Use more non-printable chars.
Edit 7: use vec for getting at tetromino data. Take advantage of the fact that the playfield has fixed dimensions. if statement => if modifier, the merging of loops of edit 2 starts paying off. Use // for the 0-score case.
Edit 8: fixed another bug, introduced in r6 (edit 5), spotted by Nakilon.
Edit 9: don't create new references when clearing lines, just move references around via array slicing. Merge two map's into one. Smarter regex. "Smarter" for. Misc golfings.
Edit 10: inlined tetromino array, added commented version.
t=[*$<]
o=0
u=->f{f.transpose}
a=u[t.reverse.join.scan /#{'( |#)'*10}/]
t.pop.split.map{|w|m=(g='I4O22Z0121T01201L31S1201J13'[/#{w[0]}\d+/].scan(/0?\d/).zip a.drop w[1].to_i).map{|r,b|(b.rindex ?#or-1)-r.size+1}.max
g.map{|r,b|b.fill ?#,m+r.size,r.to_i}
v=u[a]
v.reject!{|i|i-[?#]==[]&&(o+=10;v)<<[' ']*10}
a=u[v]}
puts u[a].reverse.map{|i|?[+i*''+?]},t[-1],o
UPDATE: Fixed a bug involving pieces that extend into the top row. Also, the output is now sent to standard out, and as a bonus, it is possible to run the script again to continue playing a game (in which case you must add up the total score yourself).
This includes nonprintable characters, so I have provided a hex dump. Save it as tetris.txt:
0000000: 7461 696c 202d 3120 245f 7c7a 6361 743e tail -1 $_|zcat>
0000010: 753b 2e20 750a 1f8b 0800 35b0 b34c 0203 u;. u.....5..L..
0000020: 5590 516b 8330 10c7 dff3 296e 4c88 ae64 U.Qk.0....)nL..d
0000030: a863 0c4a f57d 63b0 07f7 b452 88d1 b4da .c.J.}c....R....
0000040: 1a5d 5369 91a6 df7d 899a d05d 5e72 bfbb .]Si...}...]^r..
0000050: fbff 2fe1 45d5 0196 7cff 6cce f272 7c10 ../.E...|.l..r|.
0000060: 387d 477c c4b1 e695 855f 77d0 b29f 99bd 8}G|....._w.....
0000070: 98c6 c8d2 ef99 8eaa b1a5 9f33 6d8c 40ec ...........3m.@.
0000080: 6433 8bc7 eeca b57f a06d 27a1 4765 07e6 d3.......m'.Ge..
0000090: 3240 dd02 3df1 2344 f04a 0d1d c748 0bde 2@..=.#D.J...H..
00000a0: 75b8 ed0f 9eef 7bd7 7e19 dd16 5110 34aa u.....{.~...Q.4.
00000b0: c87b 2060 48a8 993a d7c0 d210 ed24 ff85 .{ `H..:.....$..
00000c0: c405 8834 548a 499e 1fd0 1a68 2f81 1425 ...4T.I....h/..%
00000d0: e047 bc62 ea52 e884 42f2 0f0b 8b37 764c .G.b.R..B....7vL
00000e0: 17f9 544a 5bbd 54cb 9171 6e53 3679 91b3 ..TJ[.T..qnS6y..
00000f0: 2eba c07a 0981 f4a6 d922 89c2 279f 1ab5 ...z....."..'...
0000100: 0656 c028 7177 4183 2040 033f 015e 838b .V.(qwA. @.?.^..
0000110: 0d56 15cf 4b20 6ff3 d384 eaf3 bad1 b9b6 .V..K o.........
0000120: 72be 6cfa 4b2f fb03 45fc cd51 d601 0000 r.l.K/..E..Q....
Then, at the bash command prompt, preferably with elvis rather than vim installed as vi:
$ xxd -r tetris.txt tetris.sh
$ chmod +x tetris.sh
$ cat << EOF > b
> [ ]
> [ ]
> [ ]
> [ ]
> [ # # #]
> [ ## ######]
> [==========]
> EOF
$ ./tetris.sh T2 Z6 I0 T7 2>/dev/null
-- removed stuff that is not in standard out --
[ ]
[ ]
[ ]
[# ###]
[# ### ]
[##### ####]
[==========]
10
The code self-extracts itself similarly to how executable programs compressed using the gzexe script do. Tetromino pieces are represented as sequences of vi editor commands. Character counting is used to detect collisions, and line counting is used to calculate the score.
The unzipped code:
echo 'rej.j.j.:wq!m'>I
echo '2rejh.:wq!m'>O
echo '2rej.:wq!m'>Z
echo '3rejh1.:wq!m'>T
echo 'rej.j2.:wq!m'>L
echo 'l2rej2h.:wq!m'>S
echo 'lrej.jh2.:wq!m'>J
for t
do for y in `seq 1 5`
do echo -n ${y}jk$((${t:1}+1))l|cat - ${t:0:1}|vi b>0
grep ========== m>0||break
[ `tr -cd '#'<b|wc -c` = `tr -cd '#'<m|wc -c` ]||break
tr e '#'<m>n
done
cat n>b
grep -v '##########' b>m
$((S+=10*(`wc -l < b`-`wc -l < m`)))
yes '[ ]'|head -7|cat - m|tail -7>b
done
cat b
echo $S
The original code before golfing:
#!/bin/bash
mkpieces() {
pieces=('r@j.j.j.' '2r@jh.' '2r@j.' '3r@jh1.' 'r@j.j2.' 'l2r@j2h.' 'lr@j.jh2.')
letters=(I O Z T L S J)
for j in `seq 0 9`; do
for i in `seq 0 6`; do
echo "jk$(($j+1))l${pieces[$i]}:wq! temp" > ${letters[$i]}$j
done
done
}
counthashes() {
tr -cd '#' < $1 | wc -c
}
droppiece() {
for y in `seq 1 5`; do
echo -n $y | cat - $1 | vi board > /dev/null
egrep '={10}' temp > /dev/null || break
[ `counthashes board` -eq `counthashes temp` ] || break
tr @ "#" < temp > newboard
done
cp newboard board
}
removelines() {
egrep -v '#{10}' board > temp
SCORE=$(($SCORE + 10 * (`wc -l < board` - `wc -l < temp`)))
yes '[ ]' | head -7 | cat - temp | tail -7 > board
}
SCORE=0
mkpieces
for piece; do
droppiece $piece
removelines
done
cat board
echo $SCORE
(Python 3 solution) Currently requires to set the input in the format as shown at the top (input code is not counted). I'll expand to read from file or stdin later. Now works with a prompt, just paste the input in (8 lines total).
R=range
f,p=[input()[1:11]for i in R(7)],p
for(a,b)in input().split():
t=[' '*int(b)+r+' '*9for r in{'I':'#,#,#,#','O':'##,##','Z':'##, ##','T':'###, # ','L':'#,#,##','S':' ##,##','J':' #, #,##'}[a].split(',')]
for r in R(6-len(t),0,-1):
for i in R(len(t)):
if any(a==b=='#'for(a,b)in zip(t[i],f[r+i])):break
else:
for i in R(0,len(t)):
f[r+i]=''.join(a if b!='#'else b for(a,b)in zip(t[i],f[r+i]))
if f[r+i]=='#'*10:del f[r+i];f[0:0]=[' '*10];p+=10
break
print('\n'.join('['+r+']'for r in f[:7]),p,sep='\n')
Not sure if I can save much more there. Quite a lot characters are lost from the transformation to bitfields, but that saves a lot more characters than working with the strings. Also I'm not sure if I can remove more whitespace there, but I'll try it later.
Won't be able to reduce it much more; after having the bitfield-based solution, I transitioned back to strings, as I found a way to compress it more (saved 8 characters over the bitfield!). But given that I forgot to include the L and had an error with the points inside, my character count only goes up sigh... Maybe I find something later to compress it a bit more, but I think I'm near the end. For the original and commented code see below:
field = [ input()[1:11] for i in range(7) ] + [ 0, input() ]
# harcoded tetrominoes
tetrominoes = {'I':('#','#','#','#'),'O':('##','##'),'Z':('##',' ##'),'T':('###',' # '),'L':('#','#','##'),'S':(' ##','##'),'J':(' #',' #','##')}
for ( f, c ) in field[8].split():
# shift tetromino to the correct column
tetromino = [ ' ' * int(c) + r + ' ' * 9 for r in tetrominoes[f] ]
# find the correct row to insert
for r in range( 6 - len( tetromino ), 0, -1 ):
for i in range( len( tetromino ) ):
if any( a == b == '#' for (a,b) in zip( tetromino[i], field[r+i] ) ):
# skip the row if some pieces overlap
break
else:
# didn't break, insert the tetromino
for i in range( 0, len( tetromino ) ):
# merge the tetromino with the field
field[r+i] = ''.join( a if b != '#' else b for (a,b) in zip( tetromino[i], field[r+i] ) )
# check for completely filled rows
if field[r+i] == '#' * 10:
# remove current row
del field[r+i]
# add new row
field[0:0] = [' '*10]
field[7] += 10
# we found the row, so abort here
break
# print it in the requested format
print( '\n'.join( '[' + r + ']' for r in field[:7] ) )
# and add the points = 10 * the number of redundant lines at the end
print( str( field[7] ) )
len: I have 3 len means I save 6 chars by shortening it, but I need 5 characters (L=len) for the definition + line break/other separator. - poke
d=0
e=[*$<]
e.pop.split.map{|f|f="L\003\003\007J\005\005\007O\007\007Z\007\013S\013\007I\003\003\003\003T\017\005"[/#{f[j=0]}(\W*)/,1].bytes.map{|z|?\0+?\0*f[1].hex+z.to_s(2).tr("01"," #")[1,9]}
k,f,i=i,[p]+f,e.zip(f).map{|l,m|l.bytes.zip(m.to_s.bytes).map{|n,o|j|=n&3&q=o||0;(n|q).chr}*""}until j>0
e=[]
e+=k.reject{|r|r.sum==544&&e<<r.tr(?#,?\s)&&d+=10}}
puts e,d
Note that the \000 escapes (including the null bytes on the third line) should be replaced with their actual nonprintable equivalent.
Sample input:
[ ]
[ ]
[ ]
[ ]
[ # # #]
[ ## ######]
[==========]
T2 Z6 I0 T7
Usage:
ruby1.9 tetris.rb < input
or
ruby1.9 tetris.rb input
?\s. - Nakilon
This is my first code golf, I think character count can get much lower, would be nice if experienced golfers can give me some hints.
The current version can handle playfields with different dimensions, too. The input can have linebreaks in both DOS/Windows and Unix format.
The code was pretty straightforward before optimization, the tetrominoes are stored in 4 integers that are interpreted as an (7*3)x4 bit array, the playfield is stored as-is, tiles are dropped and complete lines are removed at start and after each tile drop.
I wasn't sure how to count characters, so I used the filesize of the code with all unneccessary linebreaks removed.
EDIT 596=>581: Thanks to KitsuneYMG, everything except the %ls suggestion worked perfectly, additionally, I noticed putch instead of putchar can be used (getch somehow doesn't work) and removed all the parentheses in #define G.
EDIT 581=>556: Wasn't satisfied with the remaining for and the nested F loops, so there was some merging, changing and removing of loops, quite confusing but definitely worth it.
EDIT 556=>517: Finally found a way to make a an int array. Some N; merged with c, no break anymore.
EDIT 496=>471: Playfield width and height fixed now.
EDIT 471=>461: Minor modifications, putchar used again as putch is no standard function.
EDIT: Bugfix, complete lines were removed before tile drop instead of after, so complete lines could be left at the end. Fix doesn't change the character count.
#define N (c=getchar())
#define G T[j%4]&1<<t*3+j/4
#define X j%4*w+x+j/4
#define F(x,m) for(x=0;x<m;x++)
#define W while
T[]={916561,992849,217,1},C[99],c,i,j,s,t,x,A,a[99],w=13;
main(){F(j,7)C["IJLSTZO"[j]]=j;
F(j,91)a[j]=N;
W(N>w){t=C[c];x=N-86;
W(c){F(j,12)if(G&&X>1?a[X]-32:0)c=0;
F(j,12)if(G&&X>w&&!c)a[X-w]=35;x+=w;}N;
F(i,6){A=0;t=i*w;F(x,w)A|=(a[t+x]==32);
if(!A){s++;F(j,t)a[t+w-j]=a[t-j];
x=1;W(a[x]-93)a[x++]=32;}}}
F(i,91)putchar(a[i]);printf("%i0",s);}
for as #define F(x,m) for(x=0;x++<m;)? It works on C#... :P - BrunoLM
F(x,3){printf("%i",x} prints 12 instead of 012 with this change. Could change to for(x=-1;x++<m;), but this doesn't save anything :) - schnaader
printf("%03i",x) ? - Nakilon
for(x=0;x++<m;) skips 0 and so I can't use it in my code :) - schnaader
#include directives are redundant here. - Michael Foukarakis
a[99] an int (a move it to the above line with a comma) and use %ls to printf it. - KitsuneYMG
if(c==10) could be if(c<11) since none of the characters under 9 are valid as input - KitsuneYMG
(c=getchar()) and remove all c=N lines saving 6 chars. Unless I'm wrong about these, you should get t down to 585 - KitsuneYMG
main() construct works), thanks! - schnaader
#coding:l1
exec'xÚEPMO!½ï¯ i,P*Ýlš%ì‰=‰Ö–*†þz©‰:‡—Lò¾fÜ”bžAù,MVi™.ÐlǃwÁ„eQL&•uÏÔ‹¿1O6ǘ.€LSLÓ’¼›î”3òšL¸tŠv[ѵl»h;ÁºŽñÝ0Àë»Ç‡ÛûH.ª€¼âBNjr}¹„V5¾3Dë@¼¡•gO. ¾ô6 çÊsÃЮürÃ1&›ßVˆùZ`Ü€ÿžcx±ˆ‹sCàŽ êüRô{U¯ZÕDüE+³ŽFA÷{CjùYö„÷¦¯Î[0þøõ…(Îd®_›â»E#–Y%’›”ëýÒ·X‹d¼.ß9‡kD'.decode('zip')
The single newline is required, and I've counted it as one character.
Browser code-page mumbo jumbo might prevent a successful copy-and-paste of this code, so you can optionally generate the file from this code:
s = """
23 63 6F 64 69 6E 67 3A 6C 31 0A 65 78 65 63 27 78 DA 45 50 4D 4F 03 21
10 BD EF AF 20 69 2C 50 2A 02 DD 6C 9A 25 EC AD 07 8D 89 07 3D 89 1C D6
96 2A 86 05 02 1B AD FE 7A A9 89 3A 87 97 4C F2 BE 66 DC 94 62 9E 41 F9
2C 4D 56 15 69 99 0F 2E D0 6C C7 83 77 C1 16 84 65 51 4C 26 95 75 CF 8D
1C 15 D4 8B BF 31 4F 01 36 C7 98 81 07 2E 80 4C 53 4C 08 D3 92 BC 9B 11
EE 1B 10 94 0B 33 F2 9A 1B 4C B8 74 8A 9D 76 5B D1 B5 6C BB 13 9D 68 3B
C1 BA 8E F1 DD 30 C0 EB BB C7 87 DB FB 1B 48 8F 2E 1C AA 80 19 BC E2 42
4E 6A 72 01 7D B9 84 56 35 BE 33 44 8F 06 EB 40 BC A1 95 67 4F 08 2E 20
BE F4 36 A0 E7 CA 73 C3 D0 AE FC 72 C3 31 26 9B DF 56 88 AD F9 5A 60 DC
80 FF 9E 63 78 B1 88 8B 73 43 E0 8E A0 EA FC 52 F4 7B 55 8D AF 5A 19 D5
44 FC 45 2B B3 8E 46 9D 41 F7 7B 43 6A 12 F9 59 F6 84 F7 A6 01 1F AF CE
5B 30 FE F8 F5 85 28 CE 64 AE 5F 9B E2 BB 45 23 96 59 25 92 9B 94 EB FD
10 D2 B7 58 8B 64 BC 2E DF 39 87 6B 44 27 2E 64 65 63 6F 64 65 28 27 7A
69 70 27 29
"""
with open('golftris.py', 'wb') as f:
f.write(''.join(chr(int(i, 16)) for i in s.split()))
intetris
[ ] [ ] [ ] [ ] [ # # #] [ ## ######] [==========] T2 Z6 I0 T7
Newlines must be Unix-style (linefeed only). A trailing newline on the last line is optional.
To test:
> python golftris.py < intetris [ ] [ ] [ ] [# ###] [# ### ] [##### ####] [==========] 10
This code unzips the original code, and executes it with exec. This decompressed code weighs in at 366 characters and looks like this:
import sys
r=sys.stdin.readlines();s=0;p=r[:1];a='[##########]\n'
for l in r.pop().split():
n=int(l[1])+1;i=0xE826408E26246206601E>>'IOZTLSJ'.find(l[0])*12;m=min(zip(*r[:6]+[a])[n+l].index('#')-len(bin(i>>4*l&31))+3for l in(0,1,2))
for l in range(12):
if i>>l&2:c=n+l/4;o=m+l%4;r[o]=r[o][:c]+'#'+r[o][c+1:]
while a in r:s+=10;r.remove(a);r=p+r
print''.join(r),s
Newlines are required, and are one character each.
Don't try to read this code. The variable names are literally chosen at random in search of the highest compression (with different variable names, I saw as much as 342 characters after compression). A more understandable version follows:
import sys
board = sys.stdin.readlines()
score = 0
blank = board[:1] # notice that I rely on the first line being blank
full = '[##########]\n'
for piece in board.pop().split():
column = int(piece[1]) + 1 # "+ 1" to skip the '[' at the start of the line
# explanation of these three lines after the code
bits = 0xE826408E26246206601E >> 'IOZTLSJ'.find(piece[0]) * 12
drop = min(zip(*board[:6]+[full])[column + x].index('#') -
len(bin(bits >> 4 * x & 31)) + 3 for x in (0, 1, 2))
for i in range(12):
if bits >> i & 2: # if the current cell should be a '#'
x = column + i / 4
y = drop + i % 4
board[y] = board[y][:x] + '#' + board[y][x + 1:]
while full in board: # if there is a full line,
score += 10 # score it,
board.remove(full) # remove it,
board = blank + board # and replace it with a blank line at top
print ''.join(board), score
The crux is in the three cryptic lines I said I'd explain.
The shape of the tetrominoes is encoded in the hexadecimal number there. Each tetronimo is considered to occupy a 3x4 grid of cells, where each cell is either blank (a space) or full (a number sign). Each piece is then encoded with 3 hexadecimal digits, each digit describing one 4-cell column. The least significant digits describe the left-most columns, and the least significant bit in each digit describes the top-most cell in each column. If a bit is 0, then that cell is blank, otherwise it's a '#'. For example, the I tetronimo is encoded as 00F, with the four bits of the least-significant digit set on to encode the four number signs in the left-most column, and the T is 131, with the top bit set on the left and the right, and the top two bits set in the middle.
The entire hexadecimal number is then shift one bit to the left (multiplied by two). This will allow us to ignore the bottom-most bit. I'll explain why in a minute.
So given the current piece from the input, we find the index into this hexadecimal number where the 12 bits describing it's shape begin, then shift that down so that bits 1–12 (skipping bit 0) of the bits variable describe the current piece.
The assignment to drop determines how many rows from the top of the grid the piece will fall before landing on other piece fragments. The first line finds how many empty cells there are at the top of each column of the playing field, while the second finds the lowest occupied cell in each column of the piece. The zip function returns a list of tuples, where each tuple consists of the nth cell from each item in the input list. So, using the sample input board, zip(board[:6] + [full]) will return:
[
('[', '[', '[', '[', '[', '[', '['),
(' ', ' ', ' ', ' ', ' ', ' ', '#'),
(' ', ' ', ' ', ' ', '#', '#', '#'),
(' ', ' ', ' ', ' ', ' ', '#', '#'),
(' ', ' ', ' ', ' ', ' ', ' ', '#'),
(' ', ' ', ' ', ' ', ' ', '#', '#'),
(' ', ' ', ' ', ' ', ' ', '#', '#'),
(' ', ' ', ' ', ' ', '#', '#', '#'),
(' ', ' ', ' ', ' ', ' ', '#', '#'),
(' ', ' ', ' ', ' ', ' ', '#', '#'),
(' ', ' ', ' ', ' ', '#', '#', '#'),
(']', ']', ']', ']', ']', ']', ']')
]
We select the tuple from this list corresponding to the appropriate column, and find the index of the first '#' in the column. This is why we appended a "full" row before calling zip, so that index will have a sensible return (instead of throwing an exception) when the column is otherwise blank.
Then to find the lowest '#' in each column of the piece, we shift and mask the four bits that describe that column, then use the bin function to turn that into a string of ones and zeros. The bin function only returns significant bits, so we need only calculate the length of this string to find the lowest occupied cell (most significant set bit). The bin function also prepends '0b', so we have to subtract that. We also ignore the least significant bit. This is why the hexadecimal number is shift one bit to the left. This is to account for empty columns, whose string representations would have the same length as a column with only the top cell full (such as the T piece).
For example, the columns of the I tetromino, as mentioned earlier, are F, 0, and 0. bin(0xF) is '0b1111'. After ignoring the '0b', we have a length of 4, which is correct. But bin(0x0) is 0b0. After ignoring the '0b', we still have a length of' 1, which is incorrect. To account for this, we've added an additional bit to the end, so that we can ignore this insignificant bit. Hence, the +3 in the code is there to account for the extra length taken up by the '0b' at the beginning, and the insignificant bit at the end.
All of this occurs within a generator expression for three columns ((0,1,2)), and we take the min result to find the maximum number of rows the piece can drop before it touches in any of the three columns.
The rest should be pretty easy to understand by reading the code, but the for loop following these assignments adds the piece to the board. After this, the while loop removes full rows, replacing them with blank rows at the top, and tallies the score. At the end, the board and score are printed to the output.
... and does not even use code-zipping chicanery.
import os
r=os.read
b='[%11c\n'%']'*99+r(0,91)
for k,v in r(0,99).split():
t=map(ord,' -:G!.:; -:; !-.!"-. !". !./')['IJLOSTZ'.find(k)*4:][:4];v=int(v)-31
while'!'>max(b[v+j+13]for j in t):v+=13
for j in t:b=b[:v+j]+'#'+b[v+j+1:]
b=b.replace('[##########]\n','')
print b[-91:],1060-10*len(b)/13
On the test example
[ ]
[ ]
[ ]
[ ]
[ # # #]
[ ## ######]
[==========]
T2 Z6 I0 T7
it outputs
[ ]
[ ]
[ ]
[# ###]
[# ### ]
[##### ####]
[==========]
10
PS. fixed a bug pointed out by Nakilon at cost of +5
[1] http://esolangs.org/wiki/Esoteric_programming_languageI'm sure this could be improved, I'm kind of new to Golfscript.
[39 26.2/0:$14{.(}:?~1?15?1?14 2??27?13.!14?2?27?14 1]4/:t;n/)\n*:|;' '/-1%.,:c;~{)18+:&;'XIOZTLSJX'\%~;,1-t\={{.&+.90>{;.}*|\=32=!{&13-:&;}*}%}6*{&+}/|{\.@<'#'+\)|>+}4*{'['\10*']'++}:
;n/0\~n+:|;0\{.'#'
={;)}{n+|+:|;}if\.}do;' '
n+\.@*|+\$+:$;.,1-<:|;}c*|n?$*
End of lines are relevant (there shouldn't be one at the end). Anyway, here are some of the test cases I used:
> cat init.txt [ ] [ ] [ ] [ ] [ # # #] [ ## ######] [==========] T2 Z6 I0 T7> cat init.txt | ruby golfscript.rb tetris.gsc [ ] [ ] [ ] [# ###] [# ### ] [##### ####] [==========] 10 > cat init.txt [ ] [ ] [ ] [ ] [ # # #] [ ## ##### ] [==========] I0 O7 Z1 S4> cat init.txt | ruby golfscript.rb tetris.gsc [ ] [ ] [ ] [# ] [### #### ] [### ##### ] [==========] 10 > cat init.txt [ ] [ ] [ ] [ ## ### ] [ # # ] [ ## ######] [==========] T7 I0 I3> cat init.txt | ruby golfscript.rb tetris.gsc [ ] [ ] [ ] [ ] [# # ] [## # # # ] [==========] 20
Note that there is no end of line in the input file, an end of line would break the script as is.
b to |, o to &. Moved variable a initialization earlier. Removed some whitespace: n 10 to n.(, 15 14 to 15.(, etc. Didn't actually bother understanding the code though :P - Nabb
.( as ? to save characters. Enough of your code, off to write my own now :P - Nabb
open String let w=length let c s=let x=ref 0in iter(fun k->if k='#'then incr x)s;!x open List let(@),g,s,p,q=nth,ref[],ref 0,(0,1),(0,2)let l=length let u=Printf.printf let rec o x i j=let a=map(fun s->copy s)!g in if snd(fold_left(fun(r,k)(p,l)->let z=c(a@r)in blit(make l '#')0(a@r)(i+p)l;if c(a@r)=z+l then r+1,k else r,false)(j-l x+1,true)x)then g:=a else o x i(j-1)and f x=let s=read_line()in if s.[1]='='then g:=rev x else f(sub s 1 10::x)let z=f [];read_line();;for i=0to w z/3 do o(assoc z.[i*3]['I',[p;p;p;p];'O',[q;q];'Z',[q;1,2];'T',[0,3;1,1];'L',[p;p;q];'S',[1,2;q];'J',[1,1;1,1;q]])(Char.code z.[i*3+1]-48)(l!g-1);let h=l!g in g:=filter(fun s->c s<>w s)!g;for i=1to h-(l!g)do incr s;g:=make 10' '::!g done;done;iter(fun r->u"[%s]\n"r)!g;u"[==========]\n";u"%d\n"(!s*10)
My first attempt at code golf, so there are probably many tricks that I don't know yet. I left some newlines there to keep some residual "readability" (I counted newlines as 2 bytes, so removing 6 unnecessary newlines gains 12 more characters).
In input, first put the shapes then the field.
(let(b(s 0)m(e'(0 1 2 3 4 5 6 7 8 9)))
(labels((o(p i)(mapcar(lambda(j)(+ i j))p))(w(p r)(o p(* 13 r)))(f(i)(find i b))
(a(&aux(i(position(read-char)"IOZTLSJ")))(when i(push(o(nth i'((0 13 26 39)(0 1 13 14)(0 1 14 15)(0 1 2 14)(0 13 26 27)(1 2 13 14)(1 14 26 27)))(read))m)(a))))
(a)(dotimes(i 90)(if(find(read-char)"#=")(push i b)))(dolist(p(reverse m))
(setf b`(,@b,@(w p(1-(position-if(lambda(i)(some #'f(w p i)))e)))))
(dotimes(i 6)(when(every #'f(w e i))(setf s(1+ s)b(mapcar(lambda(k)(+(if(>(* 13 i)k)13(if(<=(* 13(1+ i))k)0 78))k))b)))))
(dotimes(i 6)(format t"[~{~:[ ~;#~]~}]
"(mapcar #'f(w e i))))(format t"[==========]
~a0"s)))
Testing
T2 Z6 I0 T7
[ ]
[ ]
[ ]
[ ]
[ # # #]
[ ## ######]
[==========]
[ ]
[ ]
[ ]
[# ###]
[# ### ]
[##### ####]
[==========]
10
NIL
A first attempt. Have done it with IronRuby. I'm sure it can be improved, but I really should get some work done today!
p,q,r,s=(0..9),(0..2),(0..6),0
t=[*$<]
f=p.map{|a|g=0;r.map{|b|g+=2**b if t[6-b][a+1]==?#};g}
t.pop.split.map{|x|w,y=[15,51,306,562,23,561,113]["IOZTLSJ"=~/#{x[0]}/],x[1].to_i
l=q.map{|d|r.inject{|b,c|f[d+y]&(w>>(d*4)&15-c+1)>0?c:b}}.max
q.map{|b|f[b+y]|=w>>(b*4)&15-l}
r.map{i=f.inject{|a,b|a&b};f.map!{|a|b=i^(i-1);a=((a&~b)>>1)+(a&(b>>1))};s+=i>0?10:0}}
p.map{|a|r.map{|b|t[6-b][a+1]=f[a]&2**b>0??#:' '}}
puts t,s
Testing
cat test.txt | ruby tetris.rb
[ ]
[ ]
[ ]
[ ]
[# ###]
[# ### ]
[##### ####]
[==========]
10
Edit Now using normal ruby. Got the walls output..
Z={I:?#*4,J:'#,###',L:'###,#',O:'##,##',S:'#,##, #',Z:' #,##,#',T:' #,##, #'}
t=[*$<]
R=->s{s.reverse}
T=->m{m.transpose}
a = T[R[t].join.scan /.#{'(\D)'*10}.$/]
t.pop.split.each{|z|
t,o=Z[z[0].to_sym].split(',').map{|x|x.split //},z[1].to_i
r=0..t.size-1
y=r.map{|u|1+a[o+u].rindex(?#).to_i-t[u].count(' ')}.max
(0..3).each{|i|r.each{|j|t[j][i]==?#&&a[o+j][y+i]=t[j][i]}}}
s=0
a.each{|x|s=a.max_by(&:size).size;x[s-=1]||=' 'while s>0}
a=R[T[a].reject{|x|x*''=~/[#]{10}/&&s+=10}.map{|x|?[+x*''+?]}[0..6]]
puts (0..8-a.size).map{?[+' '*10+?]},a,s
Testing:
cat test.txt | ruby 3858384_tetris.rb
[ ]
[ ]
[ ]
[ ]
[# ###]
[# ### ]
[##### ####]
[==========]
10
a.each{|x|s=a.max_by(&:size).size;x[s-=1]||=' 'while s>0} - glebm
T2 ...and then the start position. - Nakilon+500bonus though ;-) - ChristopheDcode-golfin your profile). You shant be swift dispatching justice in areas you are a "casual observer". What makes you think i "derided" others work? What i said is that I am puzzled that usually solutions are notably shorter. For each <problem, language> pair there is a kind oflimit inferiorto which solutions tend to converge, eventually. In regards to explanations, pls just ask what is unclear (on condition that you know the language already, since "those margins are too narrow to contain" a full tutorial). - Nas Banov