port of PYSWIP package.

packages/pyswip/examples/sudoku/sudoku.pl

@@ -0,0 +1,31 @@
+
+% Prolog Sudoku Solver (C) 2007 Markus Triska (triska@gmx.at)
+% Public domain code.
+
+:- use_module(library(clpfd)).
+
+% Pss is a list of lists representing the game board.
+
+sudoku(Pss) :-
+    flatten(Pss, Ps),
+    allin(Ps, 1..9),
+    maplist(all_different, Pss),
+    Pss = [R1,R2,R3,R4,R5,R6,R7,R8,R9],
+    columns(R1, R2, R3, R4, R5, R6, R7, R8, R9),
+    blocks(R1, R2, R3), blocks(R4, R5, R6), blocks(R7, R8, R9),
+    label(Ps).
+
+columns([], [], [], [], [], [], [], [], []).
+columns([A|As],[B|Bs],[C|Cs],[D|Ds],[E|Es],[F|Fs],[G|Gs],[H|Hs],[I|Is]) :-
+    all_different([A,B,C,D,E,F,G,H,I]),
+    columns(As, Bs, Cs, Ds, Es, Fs, Gs, Hs, Is).
+
+blocks([], [], []).
+blocks([X1,X2,X3|R1], [X4,X5,X6|R2], [X7,X8,X9|R3]) :-
+    all_different([X1,X2,X3,X4,X5,X6,X7,X8,X9]),
+    blocks(R1, R2, R3).
+
+allin([],_).
+allin([Pos|Board],D) :-
+	Pos in D,
+	allin(Board,D).

packages/pyswip/examples/sudoku/sudoku.py

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+# -*- coding: utf-8 -*-
+
+from pyswip.prolog import Prolog
+from pyswip.easy import *
+
+_ = 0
+puzzle1 = [
+            [_,6,_,1,_,4,_,5,_],
+            [_,_,8,3,_,5,6,_,_],
+            [2,_,_,_,_,_,_,_,1],
+            [8,_,_,4,_,7,_,_,6],
+            [_,_,6,_,_,_,3,_,_],
+            [7,_,_,9,_,1,_,_,4],
+            [5,_,_,_,_,_,_,_,2],
+            [_,_,7,2,_,6,9,_,_],
+            [_,4,_,5,_,8,_,7,_]
+            ]
+
+
+puzzle2 = [
+            [_,_,1,_,8,_,6,_,4],
+            [_,3,7,6,_,_,_,_,_],
+            [5,_,_,_,_,_,_,_,_],
+            [_,_,_,_,_,5,_,_,_],
+            [_,_,6,_,1,_,8,_,_],
+            [_,_,_,4,_,_,_,_,_],
+            [_,_,_,_,_,_,_,_,3],
+            [_,_,_,_,_,7,5,2,_],
+            [8,_,2,_,9,_,7,_,_]
+          ]
+
+def pretty_print(table):
+    print "".join(["/---", "----"*8, "\\"])
+    for row in table:
+        print "".join(["|", "|".join(" %s " % (i or " ") for i in row), "|"])
+    print "".join(["\\---", "----"*8, "/"])        
+    
+def solve(problem):
+    prolog.consult("sudoku.pl")
+    p = str(problem).replace("0", "_")
+    result = list(prolog.query("L=%s,sudoku(L)" % p, maxresult=1))
+    if result:
+        result = result[0]
+        return result["L"]
+    else:
+        return False
+    
+def main():
+    puzzle = puzzle1
+    print "-- PUZZLE --"
+    pretty_print(puzzle)    
+    print
+    print " -- SOLUTION --"
+    solution = solve(puzzle)
+    if solution:
+        pretty_print(solution)
+    else:
+        print "This puzzle has no solutions [is it valid?]"
+
+if __name__ == "__main__":
+    prolog = Prolog()
+    main()

packages/pyswip/examples/sudoku/sudoku_daily.py

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+# -*- coding: utf-8 -*-
+
+# Sudoku auto-solver. Get today's sudoku at http://www.sudoku.org.uk/daily.asp
+# and solve it
+
+import urllib
+from HTMLParser import HTMLParser, HTMLParseError
+from pyswip.prolog import Prolog
+from pyswip.easy import *
+
+URL = "http://www.sudoku.org.uk/daily.asp"
+
+class DailySudokuPuzzle(HTMLParser):
+    def __init__(self):
+        self.puzzle = []
+        self.__in_td = False
+        HTMLParser.__init__(self)
+        
+    def handle_starttag(self, tag, attrs):
+        if tag == "td":
+            for attr in attrs:
+                if attr[0] == "class" and attr[1] == "InnerTDone":
+                    self.__in_td = True
+                    break
+        elif tag == "input":
+            if self.__in_td:
+                self.puzzle.append(0)
+                
+    def handle_endtag(self, tag):
+        if tag == "td":
+            self.__in_td = False
+            
+    def handle_data(self, data):
+        if self.__in_td:
+            self.puzzle.append(int(data))        
+
+def pretty_print(table):
+    print "".join(["/---", "----"*8, "\\"])
+    for row in table:
+        print "".join(["|", "|".join(" %s " % (i or " ") for i in row), "|"])
+    print "".join(["\\---", "----"*8, "/"])        
+
+def get_daily_sudoku(url):
+    puzzle = DailySudokuPuzzle()
+    f = urllib.urlopen(url)
+    try:
+        puzzle.feed(f.read())
+    except HTMLParseError:
+        pass
+    puzzle = puzzle.puzzle
+    return [puzzle[i*9:i*9+9] for i in range(9)]
+
+def solve(problem):
+    prolog.consult("sudoku.pl")
+    p = str(problem).replace("0", "_")
+    result = list(prolog.query("Puzzle=%s,sudoku(Puzzle)" % p, maxresult=1))
+    if result:
+        result = result[0]
+        return result["Puzzle"]
+    else:
+        return False    
+    
+if __name__ == "__main__":
+    prolog = Prolog()  # having this in `solve` bites! because of __del__
+    
+    print "Getting puzzle from:", URL
+    
+    puzzle = get_daily_sudoku(URL)
+    print "-- PUZZLE --"
+    pretty_print(puzzle)    
+    print
+    print " -- SOLUTION --"
+    solution = solve(puzzle)
+    if solution:
+        pretty_print(solution)
+    else:
+        print "This puzzle has no solutions [is it valid?]"
+