def solve(self, cnf):
s = Solution()
infile = NamedTemporaryFile(mode='w')
outfile = NamedTemporaryFile(mode='r')
io = DimacsCnf()
infile.write(io.tostring(cnf))
infile.flush()
ret = call(self.command % (infile.name, outfile.name), shell=True)
infile.close()
if ret != 10:
return s
s.success = True
lines = outfile.readlines()[1:]
for line in lines:
varz = line.split(" ")[:-1]
for v in varz:
v = v.strip()
value = v[0] != '-'
v = v.lstrip('-')
vo = io.varobj(v)
s.varmap[vo] = value
# Close deletes the tmp files
outfile.close()
return s
def solve(self, cnf):
s = Solution()
infile = NamedTemporaryFile(mode='w')
outfile = NamedTemporaryFile(mode='r')
io = DimacsCnf()
infile.write(io.tostring(cnf))
infile.flush()
ret = call(self.command % (infile.name, outfile.name), shell=True)
infile.close()
if ret != 10:
return s
s.success = True
lines = outfile.readlines()[1:]
for line in lines:
varz = line.split(" ")[:-1]
for v in varz:
v = v.strip()
value = v[0] != '-'
v = v.lstrip('-')
vo = io.varobj(v)
s.varmap[vo] = value
# Close deletes the tmp files
outfile.close()
return s
def solve(self, cnf):
s = Solution()
# NamedTemporaryFile doesn't work on Windows, see https://stackoverflow.com/questions/15169101/how-to-create-a-temporary-file-that-can-be-read-by-a-subprocess
infile, infilename = tempfile.mkstemp(suffix="cnf")
try:
io = DimacsCnf()
os.write(infile, io.tostring(cnf))
os.close(infile)
try:
cmd = self.command % (infilename.replace("\\", "/"))
check_output(cmd, stderr=STDOUT, shell=True)
# Lingeling and most SAT-solvers use a non-zero return code, which in most POSIX command indicates an error.
# That's why python raises an exception, but here it's expected
except CalledProcessError as call:
if call.returncode != 10 and call.returncode != 20:
s.error = call.output
return s
finally:
os.remove(infilename)
if call.returncode != 10:
return s
s.success = True
for line in call.output.split("\n"):
# Solution line example: v 1 -2 3 -4 5 6 0
if len(line) > 0 and line[0] == 'v':
varz = line.split(" ")[1:-1]
for v in varz:
v = v.strip()
value = v[0] != '-'
v = v.lstrip('-')
vo = io.varobj(v)
s.varmap[vo] = value
return s
def solve(self, cnf):
s = Solution()
# NamedTemporaryFile doesn't work on Windows, see https://stackoverflow.com/questions/15169101/how-to-create-a-temporary-file-that-can-be-read-by-a-subprocess
infile, infilename = tempfile.mkstemp(suffix="cnf")
try:
io = DimacsCnf()
os.write(infile, io.tostring(cnf))
os.close(infile)
try:
cmd = self.command % (infilename.replace("\\","/"))
check_output(cmd, stderr=STDOUT, shell=True)
# Lingeling and most SAT-solvers use a non-zero return code, which in most POSIX command indicates an error.
# That's why python raises an exception, but here it's expected
except CalledProcessError as call:
if call.returncode != 10 and call.returncode != 20:
s.error = call.output
return s
finally:
os.remove(infilename)
if call.returncode != 10:
return s
s.success = True
for line in call.output.split("\n"):
# Solution line example: v 1 -2 3 -4 5 6 0
if len(line) > 0 and line[0] == 'v':
varz = line.split(" ")[1:-1]
for v in varz:
v = v.strip()
value = v[0] != '-'
v = v.lstrip('-')
vo = io.varobj(v)
s.varmap[vo] = value
return s
def solve(self, cnf):
s = Solution()
with NamedTemporaryFile(mode='w') as infile, \
NamedTemporaryFile(mode='r') as outfile:
io = DimacsCnf()
infile.write(io.tostring(cnf))
infile.flush()
try:
output = check_output(
[self.command, infile.name, outfile.name],
universal_newlines=True, timeout=self.timeout)
except CalledProcessError as ex:
s.success = (ex.returncode == 10)
output = ex.output
s.stats = parse_stats(output)
if not s.success:
return s
lines = outfile.readlines()[1:]
for line in lines:
varz = line.split(" ")[:-1]
for v in varz:
v = v.strip()
value = v[0] != '-'
v = v.lstrip('-')
vo = io.varobj(v)
s.varmap[vo] = value
return s
def propositional_nqueens(n):
rules = 0
t1 = time()
exprs = Cnf()
queens_by_point = {}
queens_by_name = {}
points_by_name = {}
by_rows = [[] for x in xrange(n)]
by_cols = [[] for x in xrange(n)]
for point in points(n):
name = 'queen_%d_%d' % point
by_rows[point[1]].append(name)
by_cols[point[0]].append(name)
queen = Variable(name)
queens_by_point[point] = queen
queens_by_name[name] = queen
points_by_name[name] = point
for row_of_names in by_rows:
orexp = Cnf()
for name in row_of_names:
orexp = orexp | queens_by_name[name]
rules += 1
exprs &= orexp
for col_of_names in by_cols:
orexp = Cnf()
for name in col_of_names:
orexp |= queens_by_name[name]
rules += 1
exprs &= orexp
for row in xrange(n):
for col in xrange(n):
antecedent_name = by_rows[row][col]
consequent_names = [by_rows[row][a] for a in xrange(n) if a != col]
# queen_X_Y => (not(queen_X1_Y1) & not(queen_X2_Y2))
# translates to
# (not(queen_X_Y) or not(queen_X1_Y1)) and (not(queen_X_Y) or not(queen_X2_Y2))
#andexpr = Cnf()
#for name in consequent_names:
#andexpr &= (-queens_by_name[name])
#exprs &= (queens_by_name[antecedent_name] >> andexpr)
for name in consequent_names:
rules += 1
exprs &= -queens_by_name[antecedent_name] | -queens_by_name[name]
for col in xrange(n):
for row in xrange(n):
antecedent_name = by_cols[col][row]
consequent_names = [by_cols[col][a] for a in xrange(n) if a != row]
# queen_X_Y => (not(queen_X1_Y1) & not(queen_X2_Y2))
# translates to
# (not(queen_X_Y) or not(queen_X1_Y1)) and (not(queen_X_Y) or not(queen_X2_Y2))
#andexpr = Cnf()
#for name in consequent_names:
#andexpr &= (-queens_by_name[name])
#exprs &= (queens_by_name[antecedent_name] >> andexpr)
for name in consequent_names:
rules += 1
exprs &= -queens_by_name[antecedent_name] | -queens_by_name[name]
for point1 in points(n):
for point2 in points(n):
if point1 == point2:
continue
if are_diagonal(point1, point2):
rules += 1
#exprs &= (queens_by_point[point1] >> (-queens_by_point[point2]))
exprs &= -queens_by_point[point1] | -queens_by_point[point2]
for point in points(n):
for slope in points(n, 1, 1):
if slope == (1,1):
continue
lines = [ ]
line = points_along_line(point, slope[0], slope[1], n)
if len(line) >= 2:
lines.append(line)
line = points_along_line(point, -slope[0], slope[1], n)
if len(line) >= 2:
lines.append(line)
if len(lines) == 0:
continue
for points1 in lines:
for point1 in points1:
#andexpr = Cnf()
for point2 in points1:
if point2 != point1:
#andexpr &= (-queens_by_point[point2])
rules += 1
exprs &= -queens_by_point[point] | -queens_by_point[point1] | -queens_by_point[point2]
#exprs &= ((queens_by_point[point] & queens_by_point[point1]) >> andexpr)
t2 = time()
print('# defined %d rules in %f seconds' % (rules, t2 - t1))
t1 = time()
with open('/media/rust/%d.cnf' % n, 'w') as f:
io = DimacsCnf()
f.write(io.tostring(exprs))
t2 = time()
print('# wrote rules in %f seconds' % (t2 - t1))
t1 = time()
#return
s = Minisat()
#s = Lingeling(command='/home/bburns/projects/nqueens-solver/lingeling-bal-2293bef-151109/lingeling --witness=1 --verbose=1 %s')
solution = s.solve(exprs)
t2 = time()
print('# solved in %f seconds' % (t2 - t1))
if solution.error:
raise Exception(solution.error)
if solution.success:
results = []
#for a in solution.varmap:
#if solution.varmap[a]:
#results.append(points_by_name[a.name])
for point in queens_by_point:
if solution[queens_by_point[point]]:
results.append(point)
results.sort()
return results
else:
raise Exception('Unsat.')
def propositional_nqueens(n):
rules = 0
t1 = time()
exprs = Cnf()
queens_by_point = {}
queens_by_name = {}
points_by_name = {}
by_rows = [[] for x in xrange(n)]
by_cols = [[] for x in xrange(n)]
for point in points(n):
name = 'queen_%d_%d' % point
by_rows[point[1]].append(name)
by_cols[point[0]].append(name)
queen = Variable(name)
queens_by_point[point] = queen
queens_by_name[name] = queen
points_by_name[name] = point
for row_of_names in by_rows:
orexp = Cnf()
for name in row_of_names:
orexp = orexp | queens_by_name[name]
rules += 1
exprs &= orexp
for col_of_names in by_cols:
orexp = Cnf()
for name in col_of_names:
orexp |= queens_by_name[name]
rules += 1
exprs &= orexp
for row in xrange(n):
for col in xrange(n):
antecedent_name = by_rows[row][col]
consequent_names = [by_rows[row][a] for a in xrange(n) if a != col]
# queen_X_Y => (not(queen_X1_Y1) & not(queen_X2_Y2))
# translates to
# (not(queen_X_Y) or not(queen_X1_Y1)) and (not(queen_X_Y) or not(queen_X2_Y2))
#andexpr = Cnf()
#for name in consequent_names:
#andexpr &= (-queens_by_name[name])
#exprs &= (queens_by_name[antecedent_name] >> andexpr)
for name in consequent_names:
rules += 1
exprs &= -queens_by_name[antecedent_name] | -queens_by_name[
name]
for col in xrange(n):
for row in xrange(n):
antecedent_name = by_cols[col][row]
consequent_names = [by_cols[col][a] for a in xrange(n) if a != row]
# queen_X_Y => (not(queen_X1_Y1) & not(queen_X2_Y2))
# translates to
# (not(queen_X_Y) or not(queen_X1_Y1)) and (not(queen_X_Y) or not(queen_X2_Y2))
#andexpr = Cnf()
#for name in consequent_names:
#andexpr &= (-queens_by_name[name])
#exprs &= (queens_by_name[antecedent_name] >> andexpr)
for name in consequent_names:
rules += 1
exprs &= -queens_by_name[antecedent_name] | -queens_by_name[
name]
for point1 in points(n):
for point2 in points(n):
if point1 == point2:
continue
if are_diagonal(point1, point2):
rules += 1
#exprs &= (queens_by_point[point1] >> (-queens_by_point[point2]))
exprs &= -queens_by_point[point1] | -queens_by_point[point2]
for point in points(n):
for slope in points(n, 1, 1):
if slope == (1, 1):
continue
lines = []
line = points_along_line(point, slope[0], slope[1], n)
if len(line) >= 2:
lines.append(line)
line = points_along_line(point, -slope[0], slope[1], n)
if len(line) >= 2:
lines.append(line)
if len(lines) == 0:
continue
for points1 in lines:
for point1 in points1:
#andexpr = Cnf()
for point2 in points1:
if point2 != point1:
#andexpr &= (-queens_by_point[point2])
rules += 1
exprs &= -queens_by_point[point] | -queens_by_point[
point1] | -queens_by_point[point2]
#exprs &= ((queens_by_point[point] & queens_by_point[point1]) >> andexpr)
t2 = time()
print('# defined %d rules in %f seconds' % (rules, t2 - t1))
t1 = time()
with open('/media/rust/%d.cnf' % n, 'w') as f:
io = DimacsCnf()
f.write(io.tostring(exprs))
t2 = time()
print('# wrote rules in %f seconds' % (t2 - t1))
t1 = time()
#return
s = Minisat()
#s = Lingeling(command='/home/bburns/projects/nqueens-solver/lingeling-bal-2293bef-151109/lingeling --witness=1 --verbose=1 %s')
solution = s.solve(exprs)
t2 = time()
print('# solved in %f seconds' % (t2 - t1))
if solution.error:
raise Exception(solution.error)
if solution.success:
results = []
#for a in solution.varmap:
#if solution.varmap[a]:
#results.append(points_by_name[a.name])
for point in queens_by_point:
if solution[queens_by_point[point]]:
results.append(point)
results.sort()
return results
else:
raise Exception('Unsat.')
for i in range(args.clause):
c = Cnf()
k = sample(v, args.literal)
for j in k:
if random() >= 0.5:
c |= j
else:
c |= -j
exp &= c
solver = Minisat()
solution = solver.solve(exp)
dimacsCnf = DimacsCnf()
print(dimacsCnf.tostring(exp))
if solution.error != False:
print("Error:")
print(solution.error)
elif solution.success:
print("Success:")
for i in range(args.variable):
print(v[i], solution[v[i]])
fo = open('%s.in' % (args.file_name), "w")
fo.write(dimacsCnf.tostring(exp))
fo.close()
fo = open('answer.dat', "w")
for i in range(args.variable):