i was done it , without using Arrays.sort() ---> but Time Compelxity is O(n^2) in worst case scenario :(

char ch1[] = a.toLowerCase().toCharArray(); char ch2[] = b.toLowerCase().toCharArray();

    for(int c = 0; c < ch1.length-1; c++){
        for(int cc = 0; cc < ch1.length-c-1; cc++){
            if(ch1[cc] > ch1[cc+1]){
                //swap
                char temp = ch1[cc];
                ch1[cc] = ch1[cc+1];
                ch1[cc+1] = temp;

            }
        }
    }

    String ch1_str = new String(ch1);

    // 
    for(int c = 0; c < ch2.length-1; c++){
        for(int cc = 0; cc < ch2.length-c-1; cc++){
            if(ch2[cc] > ch2[cc+1]){
                //swap
                char temp = ch2[cc];
                ch2[cc] = ch2[cc+1];
                ch2[cc+1] = temp;

            }
        }
    }

    String ch2_str = new String(ch2);


   if(ch1_str.equals(ch2_str)){
    return true;
   }

   return false;

}