Bingu was testing all the strings he had at his place and found that most of them were prone to a vicious attack by Banju, his arch-enemy. Bingu decided to encrypt all the strings he had, by the following method. Every substring of identical letters is replaced by a single instance of that letter followed by the number of occurrences of that letter. Then, the string thus obtained is further encrypted by reversing it.
Example 1:
Input:
s = "aabc"
Output: 1c1b2a
Explanation: aabc
Step1: a2b1c1
Step2: 1c1b2a
Example 2:
Input:
s = "aaaaa"
Output: 5a
Explanation: aaaaa
Step 1: a5
Step 2: 5a
Your Task:
You don't need to read input or print anything.Your task is to complete the function encryptString() which takes a single argument(s) and returns the encrypted string.
Expected Time Complexity: O(|s|).
Expected Auxiliary Space: O(|s|).
Constraints
1 <= |s| <=1000
|s| denotes the length of the string s

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