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More from Tomohiro Nishimura (19)
Lazyselect
- 8. n=8
3 Q.
5
A(n = 8)
2 7 1
p=5 A. 5
6 4 8
- 12. 1. A n (
n < 50),
A , p
. A n3/4
, B .
- 18. n 3/4
n = 500
n = 106
- 24. 2. A p B
q=pn3/4/n=pn-1/4 . , l=max{ q-
√n , 0}, h=min{ q+√n ,n3/4} ( ,
q √n ) ,B l
L h H ( B
LAZYSELECT .)
- 34. l = max{ q - √n , 0}
h = min{ q + √n , n3/4 }
- 37. 3. A , A A[i]<H A1
A2 (QUICKSORT partition
). A1 |A1| p , A2 p-|A1|
(A2 LAZYSELECT ). |A1|≧p
, A1 A[i]<L A11
A12 . |A11|≧p A11 p
(A11 LAZYSELECT ).
, A12 p-|A11| (A12 LAZYSELECT
).
- 49. A1
A11 A12 A2
LAZYSELECT LAZYSELECT LAZYSELECT
or or
p’ = p p’ = p - |A11| p’ = p - |A1|