Selection and sorting with limited storage
- 1 October 1978
- conference paper
- Published by Institute of Electrical and Electronics Engineers (IEEE)
- No. 02725428,p. 253-258
- https://doi.org/10.1109/sfcs.1978.32
Abstract
When selecting from, or sorting, a file stored on a read-only tape and the internal storage is rather limited, several passes of the input tape may be required. We study the relation between the amount of internal storage available and the number of passes required to select the Kth highest of N inputs. We show, for example, that to find the median in two passes requires at least Ω(N1/2) and at most O(N1/2 log N) internal storage. For probabilistic methods, Θ(N1/2) internal storage is necessary and sufficient for a single pass method which finds the median with arbitrarily high probability.Keywords
This publication has 1 reference indexed in Scilit:
- Time and space bounds for selection problemsPublished by Springer Nature ,1978