Approximating Reversal Distance for Strings with Bounded Number of Duplicates

For a string A = a1 . . . an, a reversal ρ(i, j), 1 ≤ i < j ≤ n, transforms the string A into a string A = a1 . . . ai−1ajaj−1 . . . aiaj+1 . . . an, that is, the reversal ρ(i, j) reverses the order of symbols in the substring ai . . . aj of A. In a case of signed strings, where each symbol is given a sign + or −, the reversal operation also flips the sign of each symbol in the reversed substring. Given two strings, A and B, signed or unsigned, sorting by reversals (SBR) is the problem of finding the minimum number of reversals that transform the string A into the string B. Traditionally, the problem was studied for permutations, that is, for strings in which every symbol appears exactly once. We consider a generalization of the problem, k-SBR, and allow

• Type: Conference
• Year: 2005
• Where: MFCS
• Authors: Petr Kolman
• Keywords: MFCS 2005, Reversal Operation, String, Substring Ai