netword.py

from pprint import pprint
from queue import Queue


w = input("Enter configuration: ")
z = w.split(" ")
paths = {}
for t in z:
    if "<->" in t:
        v = t.split("<->")
        if v[0] not in paths:
            paths[v[0]] = {v[1], v[0]}
        else:
            paths[v[0]].add(v[1])
        if v[1] not in paths:
            paths[v[1]] = {v[1], v[0]}
        else:
            paths[v[1]].add(v[0])
    elif "->" in t:
        v = t.split("->")
        if v[0] not in paths:
            paths[v[0]] = {v[1], v[0]}
        else:
            paths[v[0]].add(v[1])
    elif "<-" in t:
        v = t.split("<-")
        if v[1] not in paths:
            paths[v[1]] = {v[1], v[0]}
        else:
            paths[v[1]].add(v[0])

#pprint(paths)

def search(start, end):
    if start == end and start not in paths:
        return False
    todo = Queue()
    todo.put(start)
    visited = set()
    while not todo.empty():
        c = todo.get()
        if c == end:
            return True
        #print(c)
        visited.add(str(c))
        if c in paths:
            for path in paths[c]:
                if path not in visited:
                    todo.put(path)
    return False
v = (input("Query? "))
while v != "":
    t = v.split("->")
    if search(t[0], t[1]):
        print("Connected!")
    else:
        print("No connection.")
    v = input("Query? ")