def translate2moves(tile_solution):
"""
This function takes a tile solution
and convert it in single moves.
"""
memoized = {}
moves = []
for node in tile_solution[1:]:
if not node.action in memoized:
p = TileProblem(node.action, node.action.getGoal())
end_node = depth_first_tree_search(p)
assert end_node != None
reloc_moves = end_node.path()
reloc_moves.reverse()
memoized[node.action] = reloc_moves
displacement = (node.action.boardStart[0] - node.action.start[0],
node.action.boardStart[1] - node.action.start[1])
moves.extend([mv.action.displace(displacement) for mv in memoized[node.action][1:]])
return moves
# Solve the nQueens problem by using depth-first search
from time import time
from datetime import timedelta
from aima.search import depth_first_tree_search, NQueensProblem, Problem
def secondsToStr(t):
return str(timedelta(seconds=t))
def now():
return secondsToStr(time())
# 1. Set up the problem and set the starting time
n = 30
print "\nStarting at at " + now()[12:20]
print "problem with n =", n
start = time()
# 2. Solve the NQueens problem with depth-first search
solution = depth_first_tree_search(NQueensProblem(n))
sol = str(solution)
print "Solution: ", sol[5:len(sol) - 1]
# 3. Print time elapsed
end = time()
elapsed = end - start
print "\nElapsed time ", secondsToStr(elapsed)[0:15], "\n"