Computer product, information processing apparatus, and information search apparatus

A recording medium stores an information processing program that causes a computer having a storage unit storing therein a file group in which character code strings are described, to execute generating combined identification information by dividing into two portions, at least one among identification information for a preceding character code and identification information for a succeeding character code and respectively combining the portions with the identification information that is not divided, the preceding and succeeding character codes constituting a character code string for two-consecutive grams in a file among the file group; storing to the storage unit, various consecutive-gram divided maps obtained by allocating to each type of combined identification information generated, a string of bits corresponding to the quantity of files in the file group; and updating in the consecutive-gram divided maps, a bit indicating whether the character code string for the two-consecutive grams is present in the file.