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Graph Valid Tree
You're checking whether a set of connections forms a proper tree—one connected piece with no loops. It's a favorite in interviews because it forces you to articulate what makes a tree a tree, then verify those properties cleanly. The classic gotcha is accidentally detecting cycles when you revisit your parent node. Once you're comfortable here, connected-component problems become much easier.
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Talk through the problem while you code. Guest text is free. Hosted voice is the Own Words Pack.
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