What is a skip list and how does it speed up search?
A skip list layers 'express lanes' over a sorted linked list by randomly promoting nodes to higher levels. Instead of walking every node (O(n)), you jump along the top lanes and drop down when you overshoot, visiting only O(log n) nodes. The randomness replaces the need for rotations or complex rebalancing logic.
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Skip Lists: The Shortcut Nobody RotatesBalanced trees rebalance with rotations. Skip lists layer express lanes with random promotion—same O(log n) search, simpler locking.
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