From where are we making the combinations

#1

From where and how we are generating strings from numeric strings

how 26 turned as “co”?

#2

@alamsarfraz422 we are referring to the phone keypad for reference
2 has abc
6 has mno

"26" can possibly make the following combinations:
am
an
ao
bm
bn
bo
cm
cn
co

So if the given string is coding it can be generated from co.

Given example:

We have to search these substrings in the following set:
prateek", "sneha", "deepak", "arnav", "shikha", "palak", "utkarsh", "divyam", "vidhi", "sparsh", "akku"

3: def
4: ghi

"3 4", possible combinations:
d g
d h
d i
e g
e h
e i
f g
f h
f i

Output:

sn`eh`a
vi`dh`i
`di`vyam

I hope the question is clear now