def build_graph(n, lmbd, mu):
g = Graph()
for i in range(0, n + 1): # [0,1,2,...,n]
g.add_vertex((i))
# strelki s lambdami
for i in range(0, n):
g.add_arrow((i), (i + 1), (n - i) * lmbd)
# strelki s mu
for i in range(n, 0, -1):
g.add_arrow((i), (i - 1), mu)
return g
def build_graph(n1, n2, lmbd, mu):
g = Graph()
for i in range(0, n1 + 1):
for j in range(0, n2 + 1):
g.add_vertex((i, j))
#strelki s lambdami i mu po gorizontali
for j in range(0, n2 + 1): # 0 <= j <= n2
for i in range(0, n1): # 0 <= i <= n1-1
g.add_arrow( (i,j) , (i+1,j) , (n1 - i) * lmbd ) #strelka s lambda
g.add_arrow( (i+1,j) , (i,j) , mu ) #strelka s mu v druguu storonu
#strelki s lambdami po vertikali
for i in range(0, n1 + 1):
for j in range(0, n2):
g.add_arrow((i,j), (i,j+1), (n2 - j) * lmbd)
#strelki s mu v pervom stolbtse (t k u nas tolko odin OA)
for j in range(0, n2):
g.add_arrow((0, j+1), (0, j), mu)
return g
