Parallel Algorithms for Maximum Subsequence and Maximum Subarray
نویسندگان
چکیده
Given a sequence Q of n numbers positive and negative the maximum subsequence of Q is the contiguous subsequence that has the maximum sum among all contiguous subsequences of Q Given a two dimensional array A of n n numbers positive and negative the maximum subarray of A is the contiguous subarray that has the maximum sum among all contiguous subarrays of A We present two O log n time parallel algorithms one for nding the maximum subsequence sum of a given sequence and the other for nding the maximum subarray sum of a given array The former is optimal on an EREW PRAM The latter is optimal on a CREW PRAM in the sense that the time processor product matches the current sequential upperbound of O n
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عنوان ژورنال:
- Parallel Processing Letters
دوره 5 شماره
صفحات -
تاریخ انتشار 1995