A skip list is a probabilistic data structure that enables fast search within an ordered sequence of elements. It achieves efficiency by maintaining a linked hierarchy of subsequences. Each successive level in the hierarchy skips over fewer elements than the level above it.
Search Process:
- Searching begins at the sparsest (top) subsequence.
- The search continues until two consecutive elements are found: one smaller and one larger than or equal to the target element.
- The search then drops down to the next level of the hierarchy using the linked pointers and repeats the process.
- This continues until the search reaches the full sequence (the bottom level).
Elements to be skipped are typically chosen probabilistically, though deterministic methods also exist.