c/u puzzle solution
Suppose for example we have a couple of wordlists
words_foo, words_bar and we want
to find a c/u pair where each word might be in either list (or both).
Assuming that all the words are strings of lower-case letters,
we can find all desired pairs with the Unix command
cat words_foo words_bar | sort | uniq | grep '\<[cu]'
| sed 's/./?/' | sort | uniq -c | grep 2
If there's one wordlist words then the initial
“cat words | sort | uniq”
can be simplified to
“sort words | sort | uniq”,
and indeed the
“ | sort | uniq”
is not needed if the words are already in alphabetical order
without repetition, as is often the case.
The output will depend on how extensive your wordlist(s) might be;
the first one I tried this on contained only the canonical solution
but a larger list reported also
?lan(s), ?rania, ?rase(s), ?rate(s), ?rease(s),
?redo(s), ?retic, and ?rus(es).