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Dictionaries & sets

Key–value maps, uniqueness, counting, grouping, and fast lookups.

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Dictionaries & sets medium

How to Implement Disjoint Set Union Find in Python

Implement a Disjoint Set Union-Find data structure using a Python dictionary for parent tracking, with path compression and connectivity checks.

disjoint-set union-find graph
Python 
class DisjointSet:
    def __init__(self):
        self.parent = {}

    def find(self, x):
        # Path compression
        if self.parent[x] != x:
            self.parent[x] = self.find(self.parent[x])
        return self.parent[x]

    def union(self, x, y):
        # Initialize if not present
        if x not in…
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