def depthFirstSearch(problem):
"""
Search the deepest nodes in the search tree first.
Your search algorithm needs to return a list of actions that reaches the
goal. Make sure to implement a graph search algorithm.
To get started, you might want to try some of these simple commands to
understand the search problem that is being passed in:
print "Start:", problem.getStartState()
print "Is the start a goal?", problem.isGoalState(problem.getStartState())
print "Start's successors:", problem.getSuccessors(problem.getStartState())
"""
"*** YOUR CODE HERE ***"
startstate = problem.getStartState()
currentposition = problem.getStartState()
arewethereyet = problem.isGoalState(currentposition)
visited = [startstate]
instructions = []
plan = []
from collections import defaultdict
relations = defaultdict(list)
directions = defaultdict(list)
import numpy
from game import Directions
from game import Actions
actions = Actions()
n = Directions.NORTH
s = Directions.SOUTH
e = Directions.EAST
w = Directions.WEST
from util import Stack
stack = Stack()
while (arewethereyet == False):
successors = problem.getSuccessors(currentposition)
print("Successors for " + str(currentposition) + " are " +
str(successors))
for item in successors:
stack.push(item)
relations[currentposition].append(item[0])
moved = False
while (not moved):
poppeditem = stack.pop()
if (poppeditem[0] not in visited):
directions[poppeditem[0]] = poppeditem[1]
currentposition = poppeditem[0]
visited.append(currentposition)
moved = True
arewethereyet = problem.isGoalState(currentposition)
print("Relations = " + str(relations))
print("Length of Relations = " + str(len(relations)))
print("Directions = " + str(directions))
print("Length of Directions = " + str(len(directions)))
numhops = 0
print("Visited = " + str(visited))
print("Length of Visited = " + str(len(visited)))
for i in range(0, len(visited) - 1):
print(visited[i + 1])
print(relations[visited[i]])
if visited[i + 1] not in relations[visited[i]]:
numhops += 1
print("Number of Hops = " + str(numhops))
instructions = visited
print("Original Length of Instructions = " + str(len(instructions)))
for i in range(0, numhops):
for j in range(0, len(instructions) - 1):
if visited[j + 1] not in relations[visited[j]]:
rightend = instructions[j + 1]
rightendindex = j + 1
print("Right End = " + str(rightend))
break
for k in range(0, len(instructions) - 1):
if rightend in relations[visited[k]]:
leftend = instructions[k]
leftendindex = k
print("Left End = " + str(leftend))
break
instructions[leftendindex + 1:rightendindex] = []
print("Instructions = " + str(instructions))
print("Final Length of Instructions = " + str(len(instructions)))
for m in range(0, len(instructions) - 1):
plan.append(directions[visited[m + 1]])
print("Plan = " + str(plan))
print("Length of Plan = " + str(len(plan)))
return plan
