How can I echo characters before and after a string?

We have a string of characters and we want to find characters with second highest frequency in the string. Suggest different algorithms for this?

• e.g.  string =  abaabc output = b  (since a is appearing 3 times which is highest and b is appearing 2 times which is 2nd highest) e.g string = ababcacad output = b,c need algorithm/logic which is easy to implement for beginner. I don 't want to use hash or other kind of data structure. and so we are not concerned about space/time complexity . looking for simple array/iterative algorithm. My approach: step1 : make a structure with two member (char and int)=(character and frequency) step2: sort structure by frequency in descending order(and of-course sort corresponding characters ). step3: start printing from second index of structure if the frequency of this is not equal to 1st's frequency. ...... and so on .

• Answer:

  Make a hash function and store the frequency of alphabets in a hash table[26] ; then just go through the table to find the second highest !!