searching the .txt file

Can someone make me a really small program that searches a .txt file for a string that a person entered.For example, if a .txt file contains the String "Hello world" and the user enters "Hello world" the program could say "Found it"(or something like that)and If the program can't find it it can say "Couln't find it".

www.boost.org -> class RegEx -> GrepFiles()
if you want the esealets way! :)

be patience and you will get averythink

why not use find.exe? it is in the windows\command directory most of the time