I have an array such as A-B-C-D-E-F-G-H-I-J-K I want to rotate it N places to the right; for example, if N=3, the array should end I-J-K-A-B-C-D-E-F-G-H

Assume that the only available operation is a FLIP method that can invert any portion of the array. For example, applied to the original array FLIP(3,6) would produce A-B-F-E-D-C-G-H-I-J-K.

(In reply to A possible way by Old Original Oskar!)

I found another solution, using only three flips that all start from position 1. Start with A-B-C-D-E-F-G-H-I-J-K. Then:

FLIP(1,L-N) produces H-G-F-E-D-C-B-A-I-J-K
FLIP(1,L) produces K-J-I-A-B-C-D-E-F-G-H
FLIP(1,N) produces I-J-K-A-B-C-D-E-F-G-H

Posted by Oskar on 2004-04-19 20:56:04