| 1 | class UnionFind: |
| 2 | def __init__(self, size: int): |
| 3 | self.parent = [i for i in range(size)] |
| 4 | self.size = [1] * size |
| 5 | |
| 6 | def union(self, x: int, y: int) -> None: |
| 7 | rep_x, rep_y = self.find(x), self.find(y) |
| 8 | if rep_x != rep_y: |
| 9 | # If 'rep_x' represents a larger community, connect |
| 10 | # 'rep_y 's community to it. |
| 11 | if self.size[rep_x] > self.size[rep_y]: |
| 12 | self.parent[rep_y] = rep_x |
| 13 | self.size[rep_x] += self.size[rep_y] |
| 14 | # Otherwise, connect 'rep_x's community to 'rep_y'. |
| 15 | else: |
| 16 | self.parent[rep_x] = rep_y |
| 17 | self.size[rep_y] += self.size[rep_x] |
| 18 | |
| 19 | def find(self, x: int) -> int: |
| 20 | if x == self.parent[x]: |
| 21 | return x |
| 22 | # Path compression. |
| 23 | self.parent[x] = self.find(self.parent[x]) |
| 24 | return self.parent[x] |
| 25 | |
| 26 | def get_size(self, x: int) -> int: |
| 27 | return self.size[self.find(x)] |
| 28 | |
| 29 | |
| 30 | class MergingCommunities: |