most efficient method?

In your opinion, what is the most efficient method for locating a word within a string, then matching it to an initialized value to use in a function such as a cout? Example: word to find in string is "cat". Input to scan: " I cannot find my cat" The word "cat" is found in string and flagged, triggering a function, of say an output (cout)?
cheers,
reRanger

std::string.find()

Thanks much, Lord Thantos :)