class Graph:
def __init__(self, size):
self.size = size
self.edges = []
self.vertex_data = [''] * size
def add_edge(self, u, v, weight):
if 0 <= u < self.size and 0 <= v < self.size:
self.edges.append((u, v, weight))
def add_vertex_data(self, vertex, data):
if 0 <= vertex < self.size:
self.vertex_data[vertex] = data
def find(self, parent, i):
if parent[i] == i:
return i
return self.find(parent, parent[i])
def union(self, parent, rank, x, y):
xroot = self.find(parent, x)
yroot = self.find(parent, y)
if rank[xroot] < rank[yroot]:
parent[xroot] = yroot
elif rank[xroot] > rank[yroot]:
parent[yroot] = xroot
else:
parent[yroot] = xroot
rank[xroot] += 1
def kruskals_algorithm(self):
result = []
i = 0
self.edges = sorted(self.edges, key=lambda item: item[2])
parent, rank = [], []
for node in range(self.size):
parent.append(node)
rank.append(0)
while i < len(self.edges):
u, v, weight = self.edges[i]
i += 1
x = self.find(parent, u)
y = self.find(parent, v)
if x != y:
result.append((u, v, weight))
self.union(parent, rank, x, y)