就像是两个数相比,比如34与26,Sorting Layer决定的是十位,而Order in Layer决定的是个位,如果Sorting Layer的级别比较高,则可以忽略Order in Layer的比较,当比较的二者的Sorting Layer级别相同,…
number of passes: 1 ⌈ l o g 2 ( N / M ) ⌉ 1 \lceil log_2 (N/M) \rceil 1⌈log2(N/M)⌉ seek time: O(number of passes)
a k-way merge number of passes: 1 ⌈ l o g k ( N / M ) ⌉ 1 \lceil log_k (N/M) \rceil 1⌈logk(N/M)⌉ require 2k tapes
polyphase …