Bigrams as map keys in C++ : <p>Alright, so I'm wondering how I would go about creating a map key from a two word string (a bigram). For example, the line "This is only a test." would contain the bigrams "this is", "is only", "only a", and "a test."</p>

<p>I'm thinking of using make_pair, but something tells me this could cause these bigrams to be created out of order. Would this be the case? If not, would this pairing approach be on the right track?</p>
