[理工] [離散]-複雜度

看板Grad-ProbAsk作者 (123)時間14年前 (2010/03/02 18:26), 編輯推噓2(202)
留言4則, 3人參與, 最新討論串1/1
Suppose we have 4 algorithms designed to solve the same problem if the running time of the 4 algorithms are expressed by divide-and-conquar recurrence relations as given below ,then which algorithm would be asymptotically the best ? a) f(n) = 10f(n/3) + 10n b) f(n) = 5f(n/2) + 6n c) f(n) = 9f(n/3) + 2n^2 d) f(n) = 20f(n/5) +5n^2 10 a為θ(n^log3 ) 5 b為θ(n^log2 ) 我算d應該最好吧,解答為b!? c為θ(n^2*logn) 有人跟我看法一樣嗎...? d為θ(n^2 ) -- ※ 發信站: 批踢踢實業坊(ptt.cc) ◆ From: 122.124.202.33 ※ 編輯: gn00618777 來自: 122.124.202.33 (03/02 18:26)

03/02 18:31, , 1F
小黃解答是d,之前我也看到一份寫b的搞半天
03/02 18:31, 1F

03/02 18:45, , 2F
一份解答可以幾乎都錯真不簡單...
03/02 18:45, 2F

03/02 19:57, , 3F
log2 5不是2.多 還是我看錯了??
03/02 19:57, 3F

03/02 20:20, , 4F
我錯了~想成找大的
03/02 20:20, 4F
文章代碼(AID): #1BZEVJmN (Grad-ProbAsk)