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sudoku.pir
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sudoku.pir
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# $Id$
=pod
=head1 TITLE
Sudoku - A sudoku solver
=head1 OVERVIEW
This program implements scanning and blocked rows or columns invalidation.
It does not consider all effects of multiple number blocking, where a
combination of invalid numbers blocks a row or column. In such cases a
simple backtracking algorithm continues to solve the sudoku.
=head1 SYNOPSIS
parrot -Ot sudoku.pir [--options] [file]
If no file is given a builtin game is run.
Valid options are:
=over 4
=item --version
Print version information and exit.
=item --help
Print help hint and exit.
=item --debug
Print debug output and game progress to stdout.
=item --inv=n..
Print additionally invalid state of given number(s).
=item --pairs
Print additionally fields with uniqe pairs of numbers.
=item --builtin=name
Run builtin game. If no name is given a list of builtins is printed.
=item --nc
Use ncurses for display and single step through progress. Press any key
for next display.
=back
=head1 DESCRIPTION
The game state is held in multiple views which share one Integer PMC
per common position. Thus updating a row sets also the column or square
information. These three views are list of lists.
=head1 GAME FILES
Game files may contain comments (hash sign in the first column)
digits, and dots for empty fields. E.g:
# std020.sud
# der standard 020 - leicht
2.1..678.
...2...36
8.9.3...5
.7...4..2
..6.9.5..
9..5...6.
5...4.9.7
71...3...
.987..2.3
=head1 PARROT
=head2 Parrot features used
=over 4
=item Parrot OO
The solver is an object as well as the display.
=item Freeze/thaw
For deep copying the game state for backtracking.
=item Multi Method Dispatch
The display classes define multiple methods with the name I<print>,
which take different types and amounts of arguments.
=item Libraries
The program uses Getopt/Obj and the ncurses library.
=item Exception handling
To turn off ncurses just in case.
=back
=head2 Variable indices
Column, rows, and sqares have zero-based indices. Squares are
numbered from top left to bottom right.
=head2 Sudoku Class attributes
=over 4
=item I<rows, cols, sqrs>
LoL of 0 = free, 1..9 = number
=item I<i_rows, i_cols, i_sqrs>
LoL of a bitmask of invalid numbers per field. Bits are starting at bit
one not zero.
=item I<all>
Hash referencing these 6 items - used for backtracking.
=item I<opt>
The option hash.
=item I<disp>
Holds an instance of the display class (I<Dummy>, I<NCurses>) to use.
=back
=head1 AUTHOR
Leopold Toetsch
=head1 COPYRIGHT
Same as parrot.
=cut
.const string VERSION="0.2.3"
.sub _main :main
.param pmc argv
.local int argc
.local string raw_given
.local pmc opt
opt = parse_options(argv)
argc = elements argv
dec argc
if argc < 0 goto get_default
$I0 = defined opt["builtin"]
if $I0 goto get_default
$S0 = argv[argc]
raw_given = read_given($S0)
goto done_input
get_default:
raw_given = builtin_game(opt)
done_input:
run_game(raw_given, opt)
.end
# create game class, object, display, and run
.sub run_game
.param string raw_given
.param pmc opt
.local pmc ar
ar = verify_input(raw_given)
.local pmc cl, self, disp
cl = newclass "Sudoku"
addattribute cl, "orig"
addattribute cl, "all"
addattribute cl, "cols"
addattribute cl, "rows"
addattribute cl, "sqrs"
addattribute cl, "i_cols"
addattribute cl, "i_rows"
addattribute cl, "i_sqrs"
addattribute cl, "opt"
addattribute cl, "disp"
self = new "Sudoku"
setattribute self, "opt", opt
disp = self."new_display"()
##push_eh nc_stop
self."create"(ar)
self."display"()
$I0 = self."verify"()
unless $I0 goto err
if $I0 == 1 goto ok
if $I0 == 2 goto fin
ok:
disp."print"("init ok\n")
$I0 = self."solve"()
if $I0 == 1 goto nok
if $I0 == 0 goto nc_stop
fin:
self."display"()
disp."print"("solved\n")
disp."wait"()
nc_stop:
self."end_display"()
end
nok:
# need backtracking
.local pmc tries, all
tries = new .ResizablePMCArray
all = getattribute self, "all"
push tries, all
$I0 = self."back_track"(tries)
if $I0 == 2 goto fin
disp."print"("failed\n")
goto nc_stop
err:
printerr "inconsistent start\n"
self."end_display"()
die 3, 100
.end
# read game from file
# - ignore comment lines w/ hash sign in first col
# - valid chars are dots (empty) and digits 1..9
.sub read_given
.param string file_name
.local pmc io
.local string line, result, c
.local int i, len
result = ""
io = open file_name, "<"
$I0 = defined io
unless $I0 goto err
loop:
line = readline io
unless io goto done
c = line[0]
if c == '#' goto loop
len = length line
i = 0
lp2:
c = line[i]
if c != '.' goto no_dot
result .= c
no_dot:
if c < '1' goto no_num
if c > '9' goto no_num
result .= c
no_num:
inc i
if i < len goto lp2
goto loop
done:
.return(result)
err:
printerr "read '"
printerr file_name
printerr "' failed\n"
die 3, 100
.end
# get commandline options
.sub parse_options
.param pmc argv
load_bytecode "Getopt/Obj.pbc"
.local string prog
prog = shift argv
# Specification of command line arguments.
# --version, --debug, --inv=nnn, --builtin=name, --nc, --help
.local pmc getopts
getopts = new "Getopt::Obj"
push getopts, "version"
push getopts, "debug"
push getopts, "pairs"
push getopts, "inv=s"
push getopts, "builtin:s" # optional
push getopts, "nc"
push getopts, "help"
.local pmc opt
opt = getopts."get_options"(argv)
$I0 = defined opt['version']
unless $I0 goto n_ver
print prog
print " "
print VERSION
print "\n"
end
n_ver:
$I0 = defined opt['help']
unless $I0 goto n_help
print "usage: "
print prog
print " [options...] [file]\n"
print "see\n\tperldoc -F "
print prog
print "\nfor more\n"
end
n_help:
$I0 = defined opt['debug']
unless $I0 goto n_deb
print "debugging on\n"
n_deb:
.return (opt)
.end
.include "iterator.pasm"
# return one of the builtin games
.sub builtin_game
.param pmc opt
.local string raw_given, name
.local pmc b, it
b = get_builtins()
$I0 = exists opt["builtin"]
if $I0 goto some
$S0 = b['wikipedia']
.return ($S0)
some:
name = opt["builtin"]
if name == "1" goto list_names
if name goto sel_name
list_names:
new it, .Iterator, b
it = .ITERATE_FROM_START
loop:
unless it goto fin
$S0 = shift it
print $S0
print " "
goto loop
fin:
print_newline
end
sel_name:
$I0 = exists b[name]
if $I0 goto ok
printerr "no such builtin: '"
printerr name
printerr "'\n"
die 3, 100
ok:
$S0 = b[name]
.return ($S0)
.end
.sub get_builtins
.local pmc b
.local string raw_given
b = new Hash
# sudokusan malicious 26.6
raw_given = "..9...8.."
raw_given .= "....85..."
raw_given .= "4..23...1"
raw_given .= ".4....9.."
raw_given .= ".75...34."
raw_given .= "..2....8."
raw_given .= "1...59..4"
raw_given .= "...17...."
raw_given .= "..3...6.."
b["san_m0626"] = raw_given
# sudokusan atrocious 20.6
raw_given = "..2.1..5."
raw_given .= "95...736."
raw_given .= ".3......8"
raw_given .= ".8.6.1..."
raw_given .= "5...2...3"
raw_given .= "...7.5.1."
raw_given .= "8......3."
raw_given .= ".451...29"
raw_given .= ".1..6.4.."
b["san_a0620"] = raw_given
# sudokusan atrocious 24.6
raw_given = ".83......"
raw_given .= "....4...3"
raw_given .= "..79..8.6"
raw_given .= "....2.3.."
raw_given .= ".6.8.3.1."
raw_given .= "..5.6...."
raw_given .= "4.6..97.."
raw_given .= "3...8...."
raw_given .= "......12."
b["san_a0624"] = raw_given
# sudokusan atrocious 26.6
raw_given = "5.93....7"
raw_given .= "....9...."
raw_given .= "....64..1"
raw_given .= "..6.....5"
raw_given .= ".58...27."
raw_given .= "2.....4.."
raw_given .= "7..51...."
raw_given .= "....4...."
raw_given .= "8....61.9"
b["san_a0626"] = raw_given
# sudoku-san 4th aug 2006 - atrocious - Y-WING
raw_given = ".....1..."
raw_given .= "6..7....5"
raw_given .= ".82..49.."
raw_given .= ".734...8."
raw_given .= "........."
raw_given .= ".5...736."
raw_given .= "..16..23."
raw_given .= "9....5..1"
raw_given .= "...8....."
b["san_a0804"] = raw_given
# wikipedia - (one of ) the smallest (17 clues) known sudoku
raw_given = "1........"
raw_given .= "..274...."
raw_given .= "...5....4"
raw_given .= ".3......."
raw_given .= "75......."
raw_given .= ".....96.."
raw_given .= ".4...6..."
raw_given .= ".......71"
raw_given .= ".....1.3."
b["wikipedia"] = raw_given
# derstandard 019 schwer
raw_given = "....8..5."
raw_given .= ".123....6"
raw_given .= ".456....."
raw_given .= ".789....."
raw_given .= "5.......4"
raw_given .= ".....123."
raw_given .= ".....456."
raw_given .= "3....789."
raw_given .= ".5..3...."
b["std019"] = raw_given
# derstandard 018 mittel
raw_given = "....247.."
raw_given .= ".1.....5."
raw_given .= "..8.....3"
raw_given .= "..25....7"
raw_given .= ".4..3..8."
raw_given .= "6....91.."
raw_given .= "7.....9.."
raw_given .= ".3.....6."
raw_given .= "..581...."
b["std018"] = raw_given
# "unsolvable" 3 - Y-Wing
raw_given = "...8....6"
raw_given .= "..162.43."
raw_given .= "4...71..2"
raw_given .= "..72...8."
raw_given .= "....1...."
raw_given .= ".1...62.."
raw_given .= "1..73...4"
raw_given .= ".26.481.."
raw_given .= "3....5..."
b["uns3"] = raw_given
.return (b)
.end
# count zero bits
.sub bits0
.param int c
.local int i, n, b
i = 0
n = 0
loop:
c >>= 1 # bits start at 1
b = c & 1
if b goto is_set
inc n
is_set:
inc i
if i < 9 goto loop
.return (n)
.end
# count one bits (3 max - zero based)
.sub bits1
.param int c
.local int i, n, b
i = 0
n = 0
loop:
b = c & 1
c >>= 1
unless b goto not_set
inc n
not_set:
inc i
if i < 3 goto loop
.return (n)
.end
# make sure the game is valid
.sub verify_input
.param string raw
.local int i, c
i = length raw
if i != 81 goto len_err
.local pmc ar
ar = new .FixedIntegerArray
ar = 81
i = 0
loop:
$I0 = ord raw, i
if $I0 != 0x2e goto not_dot
c = 0
goto set_it
not_dot:
if $I0 < 0x30 goto err
if $I0 > 0x39 goto err
c = $I0 - 0x30
set_it:
ar[i] = c
inc i
if i < 81 goto loop
.return (ar)
err:
printerr "ill char: '"
$S0 = raw[i]
printerr $S0
printerr "\n"
die 3, 100
len_err:
printerr "length != 81 found : "
printerr i
printerr "\n"
die 3, 100
.end
#
# game methods
#
.namespace ["Sudoku"]
# return true if we single-step
.sub "step" :method
.local pmc opt
opt = getattribute self, "opt"
$I0 = defined opt['debug']
unless $I0 goto check_nc
.return ($I0)
check_nc:
$I0 = defined opt['nc']
.return ($I0)
.end
# return true if debugging is on
.sub "debug" :method
.local pmc opt
opt = getattribute self, "opt"
$I0 = defined opt['debug']
.return ($I0)
.end
# create 9x9 LoL
.sub create_1 :method
.param string what
.local pmc rcss, rcs, all
rcss = new .FixedPMCArray
rcss = 9
setattribute self, what, rcss
all = getattribute self, "all"
all[what] = rcss
.local int y
# create arrays
y = 0
ly1:
rcs = new .FixedPMCArray
rcs = 9
rcss[y] = rcs
inc y
if y < 9 goto ly1
.end
# create all arrays
.sub create :method
.param pmc ar
.local int x, y, p, c
.local pmc cols, rows, sqrs, e, col, row, sqr, all
.local pmc i_cols, i_rows, i_sqrs, i_col, i_row, i_sqr, inv
setattribute self, "orig", ar
all = new Hash
setattribute self, "all", all
self.create_1("rows")
self.create_1("cols")
self.create_1("sqrs")
self.create_1("i_rows")
self.create_1("i_cols")
self.create_1("i_sqrs")
rows = getattribute self, "rows"
cols = getattribute self, "cols"
sqrs = getattribute self, "sqrs"
i_rows = getattribute self, "i_rows"
i_cols = getattribute self, "i_cols"
i_sqrs = getattribute self, "i_sqrs"
# now fill em
y = 0
ly2:
x = 0
lx2:
p = y * 9
p += x
c = ar[p]
# the entries 'e' and 'inv' are common to all 3 views of the sudoku
e = new .Integer
e = c
inv = new .Integer
# set row
row = rows[y]
i_row = i_rows[y]
row[x] = e
i_row[x] = inv
# set col
col = cols[x]
i_col = i_cols[x]
col[y] = e
i_col[y] = inv
# set square
$I2 = square_of(x, y)
sqr = sqrs[$I2]
i_sqr = i_sqrs[$I2]
$I0 = x % 3
$I1 = y % 3
$I1 *= 3
$I2 = $I0 + $I1
sqr[$I2] = e
i_sqr[$I2] = inv
inc x
if x < 9 goto lx2
inc y
if y < 9 goto ly2
.end
# display
# TODO disp 2nd in different color, use curses or shell escapes
.sub display :method
.local pmc ar, rows, row, opt, disp
.local string s, c
.local int i, x, y, c1, c2, r, deb_pairs
.local string deb_n
deb_n = "" # print inv for that
self."create_inv"()
opt = getattribute self, "opt"
disp = getattribute self, "disp"
$I0 = defined opt["inv"]
unless $I0 goto no_deb
deb_n = opt["inv"]
no_deb:
deb_pairs = defined opt["pairs"]
i = 0
y = 0
s = ""
r = 0
# orig is a linear array 0..80
ar = getattribute self, "orig"
rows = getattribute self, "rows"
loop_y:
$I0 = y % 3
if $I0 goto no_line
disp."print"(r,0,"+---------+---------+---------+\n")
inc r
no_line:
row = rows[y]
x = 0
loop_x:
c1 = ar[i]
c2 = row[x]
if c1 == 0 goto ok
if c2 == 0 goto ok
if c1 != c2 goto intern_err
ok:
c = "."
if c1 == 0 goto nxt
$I0 = c1 + 0x30
c = chr $I0
goto set
nxt:
if c2 == 0 goto set
$I0 = c2 + 0x30
c = chr $I0
set:
$I0 = i % 3
if $I0 goto sp1
s .= '| '
goto sp2
sp1:
s .= ' '
sp2:
s .= c
s .= ' '
inc i
inc x
if x < 9 goto loop_x
s .= '|'
disp."print"(r,0, s)
unless deb_n goto not_deb_n
self."deb_inv"(y, deb_n)
not_deb_n:
unless deb_pairs goto not_deb_pairs
self."deb_pairs"(y)
not_deb_pairs:
disp."print"("\n")
inc r
s = ""
inc y
if y < 9 goto loop_y
disp."print"(r,0,"+---------+---------+---------+\n")
inc r
disp."wait"()
.return()
intern_err:
printerr "diff between ar and try\n"
die 3, 100
.end
# print invalid for given row and number(s)
.sub deb_inv :method
.param int y
.param string ns
.local pmc invs, inv
.local int b, x, c, i, len, n
i = 0
len = length ns
lp_inv:
$S0 = ns[i]
n = $S0
print " "
invs = getattribute self, "i_rows"
inv = invs[y]
x = 0
loop:
$I0 = x % 3
if $I0 goto nosp
print " "
nosp:
c = inv[x]
b = 1 << n
$I0 = c & b
if $I0 goto is_set
print "."
goto nxt
is_set:
print n
nxt:
inc x
if x < 9 goto loop
inc i
if i < len goto lp_inv
.end
# print pairs for given row
.sub deb_pairs :method
.param int y
.local pmc invs, inv
.local int x
print " "
invs = getattribute self, "i_rows"
inv = invs[y]
x = 0
loop:
$I0 = x % 3
if $I0 goto nosp
print " "
nosp:
.local int el, bits, i, b
el = inv[x]
bits = bits0(el)
if bits == 2 goto isa_pair
print ".."
goto nxt_x
isa_pair:
i = 1
bit_loop:
el >>= 1 # bits start at 1
b = el & 1
if b goto is_set
$I0 = i + 0x30
$S0 = chr $I0
print $S0
is_set:
inc i
if i <= 9 goto bit_loop
nxt_x:
inc x
print " "
if x < 9 goto loop
.end
# verify numbers
# returns:
# 0 ... failure
# 1 ... ok
# 2 ... finished
.sub verify :method
.local pmc rcss
.local int r, done
done = 2
rcss = getattribute self, "rows"
r = self."verify_1"(rcss)
unless r goto err
if r == 2 goto fin1
done = 1
fin1:
rcss = getattribute self, "cols"
r = self."verify_1"(rcss)
unless r goto err
if r == 2 goto fin2
done = 1
fin2:
rcss = getattribute self, "sqrs"
r = self."verify_1"(rcss)
unless r goto err
if r == 2 goto fin3
done = 1
fin3:
.return (done)
err:
.return (0)
.end
# verify rows, cols, or sqrs
.sub verify_1 :method
.param pmc rcss
.local int x, y, result
.local pmc one, e, seen, s
result = 2 # finished
y = 0
lpy:
one = rcss[y]
seen = new .Hash
x = 0
lpx:
e = one[x]
unless e goto nxtx
$I0 = exists seen[e]
unless $I0 goto not_seen
s = seen[e]
inc s
goto nxtx
not_seen:
seen[e] = 1
nxtx:
inc x
if x < 9 goto lpx
$I0 = elements seen
if $I0 == 9 goto done
result = 1
done:
$I0 = check_seen(seen)
unless $I0 goto ret_0
inc y
if y < 9 goto lpy
.return (result)
ret_0:
.return (0)
.end
# count seen in one
.sub check_seen
.param pmc seen
.local pmc it
new it, .Iterator, seen
it = .ITERATE_FROM_START
loop:
unless it goto ok
$S0 = shift it
$I0 = seen[$S0]
if $I0 > 1 goto err
goto loop
ok:
.return(1)
err:
.return(0)
.end
# create invalid bits
.sub create_inv :method
.local pmc rcss, i_rcss
rcss = getattribute self, "rows"
i_rcss = getattribute self, "i_rows"
self."create_inv_1"(rcss, i_rcss, "row")
rcss = getattribute self, "cols"
i_rcss = getattribute self, "i_cols"
self."create_inv_1"(rcss, i_rcss, "col")
rcss = getattribute self, "sqrs"
i_rcss = getattribute self, "i_sqrs"
self."create_inv_1"(rcss, i_rcss, "sqr")
.end
# create row, cols, or sqrs of invalid numbers
# one bit per invalid
.sub create_inv_1 :method
.param pmc ars
.param pmc invs
.param string what
.local int x, y, n, i, c
.local pmc ar, inv
y = 0
lpy:
ar = ars[y]
inv = invs[y]
x = 0
lpx:
c = ar[x]
unless c goto nxt_x
$P0 = inv[x]
$P0 |= 0b1111111110
nxt_x:
inc x
if x < 9 goto lpx
n = 1
lpn:
$I0 = self."contains"(ar, n)
unless $I0 goto nxt_n
i = 0
fill:
$I0 = 1 << n
$P1 = inv[i]
$P1 |= $I0
inc i
if i < 9 goto fill
nxt_n:
inc n
if n <= 9 goto lpn
self."create_inv_n"(ar, inv, y, what)
inc y
if y < 9 goto lpy
.end
# if inv contains 2 identical entries and exactly 2 nums are
# allowed these 2 positions are invalid for all other digits
.sub create_inv_n :method
.param pmc ar
.param pmc inv
.param int y
.param string what
.local int x, x1, x2, n, m, msk
.local pmc d, e1, e2, empty_2, digs
# transpose into a digit-base array with positions as bits
# this should simplify the test for 2 empty squares with
# same digit
digs = new .FixedPMCArray
digs = 9
n = 0
lpn:
msk = 2 << n
d = new .Integer
digs[n] = d
x = 0
# don't bother looking further if n is already set
$I1 = n + 1
$I0 = self."contains"(ar, $I1)
if $I0 goto nxt_n
lpx: