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DECODE STRING
MEDIUM
30 mins
Dynamic Programming
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DECODE STRING

Contributed by
Abhishek Gupta
Medium
yellow-spark
0/80
Avg time to solve 30 mins
Success Rate 50 %
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Problem Statement

A message containing letters from A-Z can be encoded into numbers using the following mapping:

'A' -> "1"
'B' -> "2"
...
'Z' -> "26"

To decode an encoded message, all the digits must be grouped then mapped back into letters using the reverse of the mapping above (there may be multiple ways).

Given a string ‘S’ containing only digits, return the number of ways to decode it.

Example:
Input: ‘S’ = "11106"

Output: 2


The possible ways are:-
(1 1 10 6),
(11 10 6)

Note that the grouping (1 11 06) is invalid because "06" cannot be mapped into 'F' since "6" is different from "06".  
Detailed explanation ( Input/output format, Notes, Constraints, Images )
Sample Input 1 :
2
12
226     
Sample Output 1 :
2
3
Explanation Of Sample Input 1 :
For the first test case:-
"12" could be decoded as "AB" (1 2) or "L" (12).

For the second test case:-
"226" could be decoded as "BZ" (2 26), "VF" (22 6), or "BBF" (2 2 6).
Sample Input 2 :
2
1234
333
Sample Output 2 :
3
1
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