string array text search

looking for algorithm for homework c++
search in a text number of sentences ending with ? or . ,words,chr.numbers of longest word and number of words in longest sentence,average chrs. number of words?
search another text in the source text and his frequency?

thanks for any advice.

Do you have anything yet? At least try to do it on your own and if you can't, then ask for help.

ý will try it with switch/case and modular programs?!