10. The method of claim 9 , wherein a distance between two character strings is calculated by a character string repetition number extractor using sim(S I ,S J )=A I,J /max(I,J) when A I,J is the number of the same characters within each character string and max(I,J) is a greater number of characters within the character strings S I and S J .
11. The method of claim 10 , wherein a degree of similarity between characters in the two character strings is calculated by the character string repetition number extractor using a(i,j)=max(a(i,j−1),a(i−1,j),a(i−1,j−1)+δ(s i ,s j )) when i and j denote characters within the two character strings and δ(s i ,s j ) indicates the sameness between characters being compared.