Design a system that takes big URLs like “http://www.geeksforgeeks.org/count-sum-of-digits-in-numbers-from-1-to-n/” and converts them into a short URL. It is given that URLs are stored in database and every URL has an associated integer id. So your program should take an integer id and generate a URL.
A URL character can be one of the following
A lower case alphabet [‘a’ to ‘z’], total 26 characters
An upper case alphabet [‘A’ to ‘Z’], total 26 characters
A digit [‘0′ to ‘9’], total 10 characters
There are total 26 + 26 + 10 = 62 possible characters.
So the task is to convert an integer (database id) to a base 62 number where digits of 62 base are "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMN
OPQRSTUVWXYZ0123456789"
Example 1:
Input:
N = 12345
Output:
dnh
12345
Explanation: "dnh" is the url for id 12345
Example 2:
Input:
N = 30540
Output:
h6K
30540
Explanation: "h6K" is the url for id 30540
Your Task:
You don't need to read input or print anything. Your task is to complete the function idToShortURL() which takes the integer n as parameters and returns an string denoting the answer.
Expected Time Complexity: O(N)
Expected Auxiliary Space: O(1)
Constraints:
1 ≤ N ≤ 10^{18}

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