I want to find the shortest path from goal
to root
working backwards
My input for root
is {'4345092': ['6570646', '40586', '484']}
My input for goal
is {'886619': ['GOAL']}
My input for path_holder
is an input but it gets converted to dct
and is used for this function. I am getting stuck regarding the while loop as it creates the path for me backwards. Right now I can't get q
to print because that part of the code isn't being ran. dct
is basically a directed graph representation that contains cycles. I can't seem to figure out how to start from GOAL
and end up at the root
node. I was wondering if someone could help me figure this out thanks!
dct:
dct =
{ '612803266': ['12408765', '46589', '5880', '31848'],
'8140983': ['7922972', '56008'],
'7496838': ['612803266'],
'1558536111': ['7496838'],
'31848': ['DEADEND'],
'1910530': ['8140983'],
'242010': ['58644', '886619'],
'727315568': ['DEADEND'],
'12408765': ['DEADEND'],
'56008': ['DEADEND'],
'58644': ['DEADEND'],
'886619': ['GOAL'],
'40586': ['931', '727315568', '242010', '1910530'],
'5880': ['1558536111'],
'46589': ['DEADEND'],
'6570646': ['2549003','43045', '13830'],
'931': ['299159122'],
'484': ['1311310', '612803266'],
'1311310': ['DEADEND'],
'7922972': ['DEADEND']
}
my function:
def backtrace(path_holder, root, goal):
dct = {}
for d in path_holder:
dct.update(d)
rootnode = root.keys()[0]
goal = goal.keys()[0]
path = []
path.append(goal)
q = 0
while goal != rootnode:
# find key that contains goal in list
for i in dct: #iterate keys
if i in dct: # prevent repeat of path
continue
for j in dct[i]: #iterate though children
if j == goal:
path.append(i)
goal = i # look for new goal
q += 1
print q
#print goal
# append key that has goal in the list
# set goal to be the key that was appended
# repeat
return path