Explain the concept of red-black trees and their properties.

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Explain the concept of red-black trees and their properties.

Red-black trees are a type of self-balancing binary search tree that maintain balance during insertions and deletions. They are named after the color assigned to each node, either red or black, which helps in maintaining balance.

The properties of red-black trees are as follows:

1. Every node is either red or black.
2. The root node is always black.
3. Every leaf (null node) is black.
4. If a node is red, both its children are black.
5. Every path from a node to its descendant leaves contains the same number of black nodes. This property is known as black height.

These properties ensure that the longest path from the root to a leaf is no more than twice the length of the shortest path, which guarantees a balanced tree. By maintaining these properties, red-black trees provide efficient operations with a worst-case time complexity of O(log n) for search, insert, and delete operations.