DIY: Group Shifted Strings

Problem statement

Given a list of strings (lowercase alphabets), we have to group all strings that are shifted versions of each other. For a string abc, its shifted sequence can be lmn because each character in both strings gets incremented by 1 to form the next character. Similarly, any three letter word that has a character difference of 1 between their letters will be shifted a sequence of abc.

Input

The input will be a list of strings. The following is an example input:

["acd", "dfg", "wyz", "yab", "mop", "bdfh", "b", "y", "moqs"]

Output

The output will be a list of grouped strings. The following is an example output:

[
["acd", "dfg" "wyz" "yab" "mop"]
["bdfh", "moqs"]
["b", "y"]
]

Coding exercise

Implement the group_strings(strs) function, where strs is the list of strings. The function will return a list of grouped strings within a list.