class UnionFind():
def __init__(self):
self.father = {
}
self.size = 0
def find(self, x):
root = x
while self.father[root] is not None:
root = self.father[root]
return root
def merge(self, x, y):
root_x = self.find(x)
root_y = self.find(y)
if root_x != root_y:
self.father[root_x] = self.father[root_y]
self.size -= 1
def add(self, x):
if x not in self.father:
self.father[x] = None
self.size += 1
uf = UnionFind()
for i in range(1, 6):
uf.add(i)
uf.merge(1, 2)
uf.merge(2, 3)
uf.merge(4, 5)
print(uf.size)
