$ sh soundex.sh fissbux
./fizzbuzz
./fizzbuzz.c
./fizzbuzz2
./fizzbuzz2.c

$ sh soundex.sh sharlok
./HackerRank/Algorithms/02-Implementation/17-sherlock_and_squares.c

$ sh soundex.sh sundek
./soundex.sh
./soundex.sed

#!/bin/sh

soundex=$( printf '%sn' "$1" | tr 'a-z' 'A-Z' | sed -f soundex.sed )

find . -exec sh -c '[ "$( printf '%sn' "${1##*/}" | tr 'a-z' 'A-Z' | sed -f soundex.sed )" = "$0" ]' "$soundex" {} ';' -print

s/[^[:alpha:]]//g
h
s/^(.).*$/1/
x
y/bfpvBFPV/11111111/
y/cgjkqsxzCGJKQSXZ/2222222222222222/
y/dtDT/3333/
y/lL/44/
y/mnMN/5555/
y/rR/66/
s/([1-6])[hwHW]1/1/g
s/([1-6])11*/1/g
s/[aeiouyhwAEIOUYHW]/!/g
s/^.//
H
x
s/n//
s/!//g
s/^(....).*$/1/
s/^(...)$/10/
s/^(..)$/100/
s/^(.)$/1000/

# Remove non-alphabetic characters
s/[^[:alpha:]]//g

# STEP 1 (part 1: retain first character)

# Save whole line in hold-space
h

# Delete everything but the first character and swap with hold-space
s/^(.).*$/1/
x

# The hold-space now contains only the first character

# STEP 2

y/bfpvBFPV/11111111/
y/cgjkqsxzCGJKQSXZ/2222222222222222/
y/dtDT/3333/
y/lL/44/
y/mnMN/5555/
y/rR/66/

# STEP 3

s/([1-6])[hwHW]1/1/g
s/([1-6])11*/1/g

# STEP 1 (part 2: remove vowels etc.)

# We don't actually remove them but "mask" them with "!"
# This avoids accidentally deleting the first character later
s/[aeiouyhwAEIOUYHW]/!/g

# Replace first character with the one saved in the hold-space

# Delete first character
s/^.//

# Append pattern-space to hold-space and swap
H
x

# Remove newline inserted by "H" above and all "!" (old vowels etc.)
s/n//
s/!//g

# STEP 4

s/^(....).*$/1/
s/^(...)$/10/
s/^(..)$/100/
s/^(.)$/1000/