question: public int search ( String txt ) { int m = pat . length ( ) ; int n = txt . length ( ) ; int i , j ; for ( i = 0 , j = 0 ; i < n && j < m ; i ++ ) { j = dfa [ txt . charAt ( i ) ] [ j ] ; } if ( j == m ) return i - m ; return n ; }
target:  Returns the index of the first occurrrence of the pattern string in the text string.