Grokking the Coding Interview: Patterns for Coding Questions
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Decode Ways (medium)

Problem Statement

You have given a string that consists only of digits. This string can be decoded into a set of alphabets where '1' can be represented as 'A', '2' as 'B', ... , '26' as 'Z'. The task is to determine how many ways the given digit string can be decoded into alphabets.


    • Input: "121"
    • Expected Output: 3
    • Justification: The string "121" can be decoded as "ABA", "AU", and "LA".
    • Input: "27"
    • Expected Output: 1
    • Justification: The string "27" can only be decoded as "BG".
    • Input: "110"




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