import fileinput,graphs
# add_edge (u -> v) with weight w to graph
def add_edge(graph,u,v,w):
if u in graph: #vertex u already in graph?
l = graph[u] #get list of neighbours
else:
graph[u] = l = list() #insert u into graph and assign an empty list of neighbours
l.append((v,w)) #append tuple (v,w) into the neighbour list
g = dict() #initialize graph
for line in fileinput.input():
u,v,w = map(int,line.split())
add_edge(g,u,v,w)
add_edge(g,v,u,w) #undirected graph, edges go both ways
print graphs.bidirectional_dijkstra(g,1,5,undirected=True) #from wikipedia
import sys,graphs,itertools
def prepare_graph():
diff_by_1 = lambda (x,y): len(x) == len(y) and sum(1 for a,b in zip(x,y) if a != b) == 1
graph = {}
for x,y in filter(diff_by_1,itertools.product(words,repeat=2)):
if x not in graph: graph[x] = []
if y not in graph: graph[y] = []
graph[x].append( ( y , 1) )
graph[y].append( ( x , 1) )
return graph
if __name__ == '__main__':
if len(sys.argv) >= 3 and len(sys.argv[1]) == len(sys.argv[2]):
src,dst = sys.argv[1:]
words = filter(lambda w : len(w) == len(src), sys.stdin.read().split()) #only consider those words with same length as parameter
if src in words and dst in words:
print graphs.bidirectional_dijkstra(prepare_graph(),src,dst,undirected=True)
else:
print "Both words should be present in the dictionary."
else:
print "Missing command line parameters."
def prepare_graph():
diff_by_1 = lambda (x, y): len(x) == len(y) and sum(1
for a, b in zip(x, y)
if a != b) == 1
graph = {}
for x, y in filter(diff_by_1, itertools.product(words, repeat=2)):
if x not in graph: graph[x] = []
if y not in graph: graph[y] = []
graph[x].append((y, 1))
graph[y].append((x, 1))
return graph
if __name__ == '__main__':
if len(sys.argv) >= 3 and len(sys.argv[1]) == len(sys.argv[2]):
src, dst = sys.argv[1:]
words = filter(
lambda w: len(w) == len(src),
sys.stdin.read().split(
)) #only consider those words with same length as parameter
if src in words and dst in words:
print graphs.bidirectional_dijkstra(prepare_graph(),
src,
dst,
undirected=True)
else:
print "Both words should be present in the dictionary."
else:
print "Missing command line parameters."
