Python/graphs/minimum_spanning_tree_kruskal.py

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from __future__ import print_function
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num_nodes, num_edges = list(map(int,input().split()))
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edges = []
for i in range(num_edges):
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node1, node2, cost = list(map(int,input().split()))
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edges.append((i,node1,node2,cost))
edges = sorted(edges, key=lambda edge: edge[3])
parent = [i for i in range(num_nodes)]
def find_parent(i):
if(i != parent[i]):
parent[i] = find_parent(parent[i])
return parent[i]
minimum_spanning_tree_cost = 0
minimum_spanning_tree = []
for edge in edges:
parent_a = find_parent(edge[1])
parent_b = find_parent(edge[2])
if(parent_a != parent_b):
minimum_spanning_tree_cost += edge[3]
minimum_spanning_tree.append(edge)
parent[parent_a] = parent_b
print(minimum_spanning_tree_cost)
for edge in minimum_spanning_tree:
print(edge)