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Implementation - Find with Compression - Disjoint Set Union (DSU) | Graph Theory | Repovive

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Graph Theory37 sections · 1633 units81h total

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Implementation - Find with Compression

Coding the Magic

You use recursion to implement Path Compression neatly.

function find(i):
    if parent[i] == i:
        return i
    parent[i] = find(parent[i])
    return parent[i]

The part parent[i] = find(...) is what flattens the tree.

This runs in $O(\alpha(n))$ amortized time and uses $O(n)$ space.