question: private static int transpositions ( final CharSequence first , final CharSequence second ) { int transpositions = 0 ; for ( int i = 0 ; i < first . length ( ) ; i ++ ) { if ( first . charAt ( i ) != second . charAt ( i ) ) { transpositions ++ ; } } return transpositions / 2 ; }
target:  Calculates the number of transposition between two strings.