1124. Decode Ways — Count Decodings

A message of digits is encoded where 'A'->1, ..., 'Z'->26. Given a digit string s, return the number of ways to decode it. A leading zero or an invalid pairing yields zero ways. The input is JSON {s}.

Input: JSON {s}.

Output: Integer — the number of decodings.

Examples

Input: {"s":"12"}
Output: 2
Explanation: 'AB' or 'L'.

Input: {"s":"226"}
Output: 3
Explanation: 'BZ', 'VF', or 'BBF'.

Input: {"s":"06"}
Output: 0
Explanation: Leading zero is invalid.

Constraints

• 1<=|s|<=100

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