Leaves Optimal Adaptive Sort LOAS and LLCP Merge

抄録

When we sort a large data base where a key is a long string of characters, reducing the number of key comparisons is very important for a sorting method. In this paper, we show that the number of key comparisons of LOAS (Leaves Optimal Adaptive Sort) is much smaller than that of MERGESORT and QUICKSORT when the number of leaves of a given data is small. Here, the leaf of a sequence stands for an element in the sequence that does not have any smaller neighbor than it. Since LOAS is a merge-based sorting algorithm, it is very important to use an efficient merging algorithm. We propose LLCP merging method which drastically reduces the number of key accesses when a key is a long character string.