5. The computer-readable recording medium according to claim 2 , wherein, the adding includes securing, in the overlap table, a region to be used for managing data with respect to each piece of the first hashed data.
2. The computer-readable recording medium according to claim 1 , wherein the adding includes, when a piece of the first hashed data obtained by N-dimensionally hashing words collides with another, registering the piece of the first hashed data in an overlap table.