Generate the Last-to-First Mapping of a String solved by 76

Sept. 22, 2015, 5:42 a.m. by Rosalind Team

The Last-to-First array, denoted LastToFirst(i), answers the following question: given a symbol at position i in LastColumn, what is its position in FirstColumn?

Last-to-First Mapping Problem

Given: A string Transform and an integer i.

Return: The position LastToFirst(i) in FirstColumn in the Burrows-Wheeler matrix if LastColumn = Transform.

Sample Dataset


Sample Output


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