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Google Kickstart 2021 Round A Solutions K-Goodness String Problem Charles defines the goodness score of a string as the number of indices ii such that Si≠SN−i+1Si≠SN−i+1 where 1≤i≤N/21≤i≤N/2 (11-indexed). For example, the string CABABC has a goodness score of 22 since S2≠S5S2≠S5 and S3≠S4S3≠S4. Charles gave Ada a string SS of length NN, consisting of uppercase letters and asked her to convert it into a string with a goodness score of KK. In one operation, Ada can change any character in the string to

Problem Reversort Note: The main parts of the statements of the problems "Reversort" and "Reversort Engineering" are identical, except for the last paragraph. The problems can otherwise be solved independently. Reversort is an algorithm to sort a list of distinct integers in increasing order. The algorithm is based on the "Reverse" operation. Each application of this operation reverses the order of some contiguous part of