def AlphaBetaWithMemory(alpha, beta, d):
if TT.has_key(board.hash):
lowerbound, upperbound = TT[board.hash]
if lowerbound >= beta:
return lowerbound
if upperbound <= alpha:
return upperbound
alpha = max(alpha, lowerbound)
beta = min(beta, upperbound)
if d == 0:
g = static.eval()
elif board.whiteToMove():
g, a = -inf, alpha # save original alpha value
for mv in legal.moves():
if g >= beta:
break
move.make(mv)
g = max(g, AlphaBetaWithMemory(a, beta, d - 1))
move.umake(mv)
a = max(a, g)
else:
assert board.blackToMove()
g, b = +inf, beta #save original beta value
for mv in legal.moves():
if g <= alpha:
break
move.make(mv)
g = min(g, AlphaBetaWithMemory(alpha, b, d - 1))
move.umake(mv)
# transition table storing of bounds
# fail low implies an upper bound
if g <= alpha:
if TT.has_key(board.hash):
lower, upper = TT[board.hash]
else:
lower, upper = -inf, +inf
TT[board.hash] = lower, g
# found an accurate minimax value - will not occur if called with zero window
if g > alpha and g < beta:
TT[board.hash] = g, g
# fail high result implies a lower bound
if g > beta:
if TT.has_key(board.hash):
lower, upper = TT[board.hash]
else:
lower, upper = -inf, +inf
TT[board.hash] = g, upper
return g
def legals():
mvs = legal.moves()
for mv in mvs:
if board.whiteToMove():
print "%s %s" % (move.num(mv), san.pr(mv, mvs))
else:
print "%s ...%s" % (move.num(mv), san.pr(mv, mvs))
def mybest_static(silent=False):
mvlist = legal.moves()
if len(mvlist) > 0:
if board.whiteToMove():
mv, score = best.forWhite(mvlist)
else:
mv, score = best.forBlack(mvlist)
if not silent:
if move.color(mv) == 'white':
msg = "After %s %s [%s]" % (move.num(mv), san.pr(
mv, mvlist), score)
else:
msg = "After %s ...%s [%s]" % (move.num(mv), san.pr(
mv, mvlist), score)
move.make(mv)
if not silent:
print msg
auto()
if verbose:
board.dump()
assert board.valid() # aggressive validation
return True
else:
print "no moves"
return False
def trymv(s):
mvs = legal.moves()
found = algebraic.find(s, mvs)
if len(found) == 0:
print "not found"
elif len(found) == 1:
move.make(found[0])
auto()
elif len(found) > 1:
print "ambiguous"
def trymv(s):
assert playing
mvs = legal.moves()
found = algebraic.find(s, mvs)
if len(found) == 0:
put_illegalmove(s, "not found")
elif len(found) == 1:
move.make(found[0])
reply() # sends the random response
elif len(found) > 1:
put_illegalmove(s, "ambiguous")
def moves(d):
mvlist = legal.moves()
if d > 0:
# sort captures to the front of the list
mvlist.sort(cmp)
return mvlist
elif d > depth2:
# after depth limit reach, we only look at a captures
return filter(lambda mv: move.tag(mv) in ["x", "x/", "xep"], mvlist)
else:
return []
def find(s):
mvs = legal.moves()
found = algebraic.find(s, mvs)
if len(found) == 0:
print " " * 13 + "no such move"
if len(found) == 1:
print " " * 13 + "found unique", san.pr(found[0], mvs)
elif len(found) > 1:
print " " * 13 + "ambiguous, choices are:"
for mv in found:
print " " * 17, san.pr(mv, mvs)
return found
def report_result():
assert len(legal.moves()) == 0
if board.whiteToMove():
if blackAttacks(board.whiteKingAt):
put_result("1-0", "black mates")
else:
put_result("1/2-1/2", "stalemate")
else:
assert board.blackToMove()
if whiteAttacks(board.blackKingAt):
put_result("0-1", "white mates")
else:
put_result("1/2-1/2", "stalemate")
def opponent_move(s):
assert engineColor in ['white', 'black', None]
assert board.colorToMove() != engineColor
mvs = legal.moves()
found = algebraic.find(s, mvs)
if len(found) == 0:
put_illegalmove(s, "not found")
elif len(found) == 1:
assert board.colorToMove() != engineColor
assert move.color(found[0]) != engineColor
move.make(found[0])
if board.colorToMove() == engineColor:
assert board.colorToMove() == engineColor
reply()
elif len(found) > 1:
put_illegalmove(s, "ambiguous")
def reply():
#if not board.colorToMove()==engineColor:
# return None
assert board.colorToMove() == engineColor
mvs = legal.moves()
#time.sleep(0.1)
if len(mvs) > 0:
if len(board.history) > 300:
resign()
else:
mv, score, cnt, sec = alphabeta.best(mvs)
s = san.pr(mv, mvs)
put_move(s)
move.make(mv)
else:
assert len(mvs) == 0
report_result()
def prline(mvs):
s = ""
c = 0
for mv in mvs:
legals = legal.moves()
if move.color(mv) == 'white':
s = s + ("%s %s" % (num(mv), san.pr(mv, legals)))
else:
if c == 0:
s = "%s ...%s " % (num(mv), san.pr(mv, legals))
else:
s = s + (" %s " % san.pr(mv, legals))
move.make(mv)
c = c + 1
while c > 0:
move.umake(board.lastMove())
c = c - 1
return s
def rand(silent=False):
mvlist = legal.moves()
if len(mvlist) > 0:
#n = random.randint(0,len(mvlist)-1)
mv = random.choice(mvlist)
if not silent:
if move.color(mv) == 'white':
msg = "After %s %s" % (move.num(mv), san.pr(mv, mvlist))
else:
msg = "After %s ...%s" % (move.num(mv), san.pr(mv, mvlist))
move.make(mv)
if not silent:
print msg
auto()
if verbose:
board.dump()
assert board.valid() # aggressive validation
return True
else:
print "no moves"
return False
def mybest():
mvlist = legal.moves()
if len(mvlist) > 0:
#mv,score,cnt,sec = alphabeta.best(mvlist)
mv, score, cnt, sec = searchfunction(mvlist)
if not silent:
if move.color(mv) == 'white':
fmt = "After %s %s [%s] searched %s positions in %s sec"
else:
fmt = "After %s ...%s [%s] searched %s positions in %s sec"
print fmt % (move.num(mv), san.pr(mv, mvlist), score, cnt, sec)
print "ttHits=%s |WTT|=%s |BTT|=%s" % (
alphabeta.ttHits, len(alphabeta.WTT), len(alphabeta.BTT))
move.make(mv)
auto()
if verbose:
board.dump()
assert board.valid() # aggressive validation
return True
else:
print "no moves"
return False
def eval():
mvs = legal.moves()
s = legal.state(mvs)
assert s in ['whiteMates', 'blackMates', 'stalemate', 'continue']
if s == 'whiteMates':
return +inf # black has been mated
elif s == 'blackMates':
return -inf # white has been mated
elif s == 'stalemate':
return 0
else:
assert s == 'continue'
ma = wmaterial() + bmaterial()
c = wcenter() + bcenter()
p = wpenalty() + bpenalty()
b = wbonus() + bbonus()
mo = wmobility(mvs) + bmobility(mvs)
k = wkingsafety() + bkingsafety()
#print "58: k=%s m=%s eval=%s" % (k,m,k+m)
tot = 3 * ma + c + p + b + mo
#tot = ma
return tot + 0.1 * random.randint(0, 9)
def reply():
global playing
assert playing
mvs = legal.moves()
if len(mvs) > 0:
mv = random.choice(mvs)
s = san.pr(mv, mvs) # use a different notation
put_move(s)
move.make(mv)
else:
assert len(mvs) == 0
playing = False
if board.whiteToMove():
if blackAttacks(board.whiteKingAt):
put_result("1-0", "white checkmated")
else:
put_result("1/2-1/2", "stalemate")
else:
assert board.blackToMove()
if whiteAttacks(board.blackKingAt):
put_result("0-1", "black checkmated")
else:
put_result("1/2-1/2", "stalemate")