class NFA:
regexp = None
m = 0
def __init__(self, regexp):
self.regexp = regexp
self.m = len(regexp)
self.graph = Digraph(self.m + 1)
ops = []
for i in range(0, self.m):
lp = i
if regexp[i] == '(' or regexp[i] == '|':
ops += [i]
elif regexp[i] == ')':
or_ = ops.pop()
if regexp[or_] == '|':
lp = ops.pop()
self.graph.addEdge(lp, or_ + 1)
self.graph.addEdge(or_, i)
elif regexp[or_] == '(':
lp = or_
else:
assert False
if i < self.m - 1 and regexp[i + 1] == '*':
self.graph.addEdge(lp, i + 1)
self.graph.addEdge(i + 1, lp)
if regexp[i] == '(' or regexp[i] == '*' or regexp[i] == ')':
self.graph.addEdge(i, i + 1)
if len(ops) != 0:
raise ValueError("Invalid regular expression")
def recognizes(self, txt):
dfs = DirectedDFS(self.graph, [0])
pc = []
for v in range(0, self.graph.Vertex()):
if dfs.marked[v]:
pc += [v]
for i in range(0, len(txt)):
if txt[i] == '*' or txt[i] == '|' or txt[i] == '(' or txt[i] == ')':
raise ValueError("text contains the metacharacter %s" %
(txt[i]))
match = []
for v in pc:
if v == self.m:
continue
if self.regexp[v] == txt[i] or self.regexp[v] == '.':
match += [v + 1]
dfs = DirectedDFS(self.graph, match)
pc = []
for v in range(0, self.graph.Vertex()):
if dfs.marked[v]:
pc += [v]
if len(pc) == 0:
return False
for v in pc:
if v == self.m:
return True
return False
class SymbolDigraph:
def __init__(self, filename, delimiter):
self.st = dict()
self.keys = dict()
delimiter = None
myin = In(filename, delimiter)
while myin.hasNextLine():
a = myin.readLine().split(delimiter)
for i in range(0, len(a)):
if self.st.get(a[i]) == None:
self.st[a[i]] = len(self.st)
for name in self.st.keys():
self.keys[self.st[name]] = name
self.graph = Digraph(len(self.st.keys()))
myin = In(filename, '\n')
while myin.hasNextLine():
a = myin.readLine().split(' ')
v = self.st.get(a[0])
for i in range(1, len(a)):
w = self.st.get(a[i])
self.graph.addEdge(v, w)
def contains(self, s):
if self.st.get(s) == None:
return False
else:
return True
def index(self, s):
return self.st.get(s)
def indexOf(self, s):
return self.get(s)
def name(self, v):
self.validateVertex(v)
return self.keys[v]
def nameOf(self, v):
self.validateVertex(v)
return self.keys[v]
def G(self):
return self.graph
def digraph(self):
return self.graph
def validateVertex(self, v):
Ver = self.graph.Vertex()
if v < 0 or v >= Ver:
raise ("vertex %d is not between 0 and %d " % (v, Ver - 1))
return self.id[v]
def check(self, G):
pass
def validateVertex(self, v):
V = len(self.marked)
if v < 0 or v >= V:
raise ("vertex %d is not between 0 and %d" % (v, V - 1))
if __name__ == '__main__':
myin = In(sys.argv[1], None)
G = Digraph(myin)
scc = KosarajuSharirSCC(G)
m = scc.mcount()
print("%d strong components" % m)
components = [None] * m
for i in range(0, m):
components[i] = []
for v in range(0, G.Vertex()):
components[scc.vid(v)].append(v)
s = ""
for i in range(0, m):
for v in components[i]:
s += "%d " % v
s += '\n'
print(s)