Replacing string characters using CLI

Question

I want to replace a few characters in a string. For eg. say replace all x,y,z with c in aabbxxddeeyyzzkk.

I know it can be done using

$string" | tr 'x' 'c' | tr 'y' 'c'

But I want some way to do this without using pipes.

Answer 1

To replace each of xy and z with c use:

echo "$string" | tr xyz c

in order to replace the repeating occurrences with a single c use:

echo "$string" | sed -r 's/[xyz]+/c/g'