DIY: Decode Ways
Explore how to decode numeric strings into letters based on a mapping from numbers to the alphabet. Understand constraints like invalid leading zeros and implement the function to count all valid decoding ways. This lesson helps you solve coding problems related to secure message interpretation and character encoding.
We'll cover the following...
We'll cover the following...
Problem statement
A message containing the letters from A-Z can be encoded into a string of numbers, using the following mapping:
'A' -> "1"
'B' -> "2"
...
'Z' -> "26"
To decode an encoded message, all the digits must be grouped and then mapped back into letters, using the reverse of the mapping ...