What is the time complexity of searching in a quadtree?

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What is the time complexity of searching in a quadtree?

The time complexity of searching in a quadtree is typically O(log n), where n represents the number of elements in the quadtree.

In a quadtree, the space is divided into four quadrants recursively, forming a tree-like structure. Each node in the quadtree represents a quadrant, and it contains either four child nodes or no child nodes. The quadtree is commonly used for spatial indexing and searching in two-dimensional space.

During a search operation in a quadtree, the algorithm starts at the root node and compares the search query with the boundaries of the current node. If the query falls completely outside the boundaries, the algorithm terminates as there is no need to search further in that particular branch. If the query falls completely inside the boundaries, the algorithm returns the elements within that node.

However, if the query intersects with the boundaries, the algorithm recursively traverses down to the child nodes until it reaches a leaf node or a node with no child nodes. This process continues until the desired elements are found or until the algorithm determines that the elements do not exist in the quadtree.

Since the quadtree divides the space into quadrants, each level of the tree reduces the search space by a factor of four. Therefore, the time complexity of searching in a quadtree is logarithmic with respect to the number of elements in the quadtree, resulting in a time complexity of O(log n).