IN-PLACE MERGING AND EXTERNAL SORTING ALGORITHM WITH NO ADDITIONAL DISK SPACE

Abstract

The performance of external sorting mainly depends on its I/O and time complexities. In this paper we represent a more efficient external sorting algorithm with no additional disk space. This algorithm uses Quick sort to produce runs in the first phase. It uses special in-place merging technique in the second phase. The algorithm excels in sorting a huge file, which is larger than the available internal memory of the computer. The algorithm creates no backup file for manipulating huge records. Usually the external sorting algorithm needs additional disk space in merging phase. This algorithm saves disk space, since it does not use any backup file or additional disk space. Here we have briefly reviewed the external sorting algorithms, which do not use additional disk space. The I/O and time complexities of the proposed algorithm are analyzed and compared with that of other similar algorithms. We have found that the I/O complexity of the proposed algorithm is less than that of other similar algorithms (algorithms which do not need additional disk space) with the same time complexity.