#!/usr/bin/env python
# encoding=utf-8 (pep 0263)
from linked_lists import Cons, Nil, member
def solution(node):
for path in depth_first_search(node):
yield path
def depth_first_search(start_node):
paths = [Cons(start_node, Nil)] # pouzijeme pythonovsky seznam jako LIFO
while len(paths) > 0:
path = paths.pop()
node = path.head
if is_goal(node):
yield path
for node1 in move_anyY(node):
if member(node1,path):
continue
paths.append(Cons(node1, path))
def is_goal(x):
# zavisi na resenem problemu
return x == "E"
graph = dict(A=["B", "E", "F"],
B=["C"], F=["C"],
C=["D"],
D=["E"])
def move_anyY(x):
# zavisi na resenem problemu
if x in graph:
for y in graph[x]:
yield y
# demonstracni vypis
if __name__ == "__main__":
print("Depth-First Search")
print("Volani next(solution('A')) : %s" % next(solution('A')))
Depth-First Search
Volani next(solution('A')) : ['E', 'D', 'C', 'F', 'A']