def detectCycleUnDgraphDisjointSets(g):
edges = []
sets = disjointSet(range(len(g.adjLst)))
for u,edgeLst in enumerate(g.adjLst): #assuming vertex numbers start from zero
for v in edgeLst:
if (v,u) not in edges:
edges.append((u,v))
if sets.find(u) != sets.find(v):
#union two sets
sets.union(u,v)
else:
return True
return False
def kruskalsMST(g,start=None):
N = len(g.adjLst)
Edges = [[u,v,w]for u, wvList in enumerate(g.adjLst) for w,v in wvList]
Edges.sort(cmp = cmpr)
TV = disjointSet(range(N))
TE = []
cost, numEdges, i = 0,0,0
while numEdges < N and i < len(Edges):
u,v,wt = Edges[i]
if TV.find(u) != TV.find(v):
TV.union(u,v)
TE.append([u,v])
cost = cost + wt
numEdges = numEdges + 1
i = i+1
return cost,TE
