public static void doLuckSubString(String str){
        int i=0,j=0,k=0;
        int fib1=1,fib2=1;
        int difnum = 0;

        for(i=0;i<str.length();i++){

            for(j=i;j<str.length();j++){
                if( i==j ){
                    difnum = 1;
                    fib1 = 1;
                    fib2 = 2;

                }else{//
                    for(k=i;k<j;k++){
                        if(str.charAt(k) == str.charAt(j)){
                            break;
                        }
                    }//end of for
                    if( k>=j ){
                        difnum++;
                        if( difnum>fib1 ){
                            int tmp = fib1;
                            fib1 = fib2;
                            fib2 = fib1 + tmp;
                        }
                    }
                }//end of else, and update difnum
                if (difnum == fib1 ) {

                    String substr = str.substring(i, j + 1);
                    String str1 = str.substring(0,j);
                    if( !str1.contains(substr)) {
                        System.out.println(substr);
                    }
                }
            }
        }
    }