Abstract
We introduce a new online algorithm for the multiselection problem which performs a sequence of selection queries on a given unsorted array. We show that our online algorithm is 1-competitive in terms of data comparisons. In particular, we match the bounds (up to lower order terms) from the optimal offline algorithm proposed by Kaligosi et al. [ICALP 2005].
We provide experimental results comparing online and offline algorithms. These experiments show that our online algorithms require fewer comparisons than the best-known offline algorithms. Interestingly, our experiments suggest that our optimal online algorithm (when used to sort the array) requires fewer comparisons than both quicksort and mergesort.
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References
Aggarwal, A., Vitter, J.S.: The input/output complexity of sorting and related problems. Commun. ACM 31(9), 1116–1127 (1988)
Barbay, J., Gupta, A., Rao, S.S., Sorenson, J.: Competitive online selection in main and external memory. CoRR, abs/1206.5336 (2012)
Belal, A., Elmasry, A.: Distribution-sensitive construction of minimum-redundancy prefix codes. In: Durand, B., Thomas, W. (eds.) STACS 2006. LNCS, vol. 3884, pp. 92–103. Springer, Heidelberg (2006)
Blum, M., Floyd, R.W., Pratt, V.R., Rivest, R.L., Tarjan, R.E.: Time bounds for selection. J. Comput. Syst. Sci. 7(4), 448–461 (1973)
Cardinal, J., Fiorini, S., Joret, G., Jungers, R.M., Munro, J.I.: An efficient algorithm for partial order production. In: STOC, pp. 93–100 (2009)
Dobkin, D.P., Munro, J.I.: Optimal time minimal space selection algorithms. J. ACM 28(3), 454–461 (1981)
Dor, D., Zwick, U.: Selecting the median. SICOMP 28(5), 1722–1758 (1999)
Hoare, C.A.R.: Algorithm 65: find. Commun. ACM 4(7), 321–322 (1961)
Jiménez, R.M., Martínez, C.: Interval sorting. In: Abramsky, S., Gavoille, C., Kirchner, C., Meyer auf der Heide, F., Spirakis, P.G. (eds.) ICALP 2010. LNCS, vol. 6198, pp. 238–249. Springer, Heidelberg (2010)
Kaligosi, K., Mehlhorn, K., Munro, J.I., Sanders, P.: Towards optimal multiple selection. In: Caires, L., Italiano, G.F., Monteiro, L., Palamidessi, C., Yung, M. (eds.) ICALP 2005. LNCS, vol. 3580, pp. 103–114. Springer, Heidelberg (2005)
Kirkpatrick, D.G., Seidel, R.: The ultimate planar convex hull algorithm. SIAM J. Comput. 15(1), 287–299 (1986)
Prodinger, H.: Multiple quickselect - Hoare’s find algorithm for several elements. Inf. Process. Lett. 56(3), 123–129 (1995)
Schönhage, A., Paterson, M., Pippenger, N.: Finding the median. J. Comput. Syst. Sci. 13(2), 184–199 (1976)
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Barbay, J., Gupta, A., Jo, S., Rao, S.S., Sorenson, J. (2013). Theory and Implementation of Online Multiselection Algorithms. In: Bodlaender, H.L., Italiano, G.F. (eds) Algorithms – ESA 2013. ESA 2013. Lecture Notes in Computer Science, vol 8125. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-40450-4_10
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DOI: https://doi.org/10.1007/978-3-642-40450-4_10
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