Given an integer N, find the sum of odd numbers and even numbers from 1 to N.

Example 1:
Input: 5
Output: 9 6
Explanation: Odd numbers upto 5 are 1, 3, 5
and their sum = 1 + 3 + 5 = 9.Even numbers
upto 5 are 2 and 4 and their sum = 2 + 4 = 6.
Example 1:
Input: 6
Output: 9 12
Explanation: Odd numbers upto 6 are 1, 3, 5
and their sum = 1 + 3 + 5 = 9.Even numbers
upto 5 are 2 , 4 and 6 and their
sum = 2 + 4 + 6 = 12.

Your Task:
You don't need to read or print anything, Your task is to complete the function find_sum() which takes N as input parameter and returns a list of two numbers where first numbers is sum of odd numbers and second number is sum of even numbers.

Expected Time Complexity: O(1)
Expected Space Complexity: O(1)

Constraints:
1 <= N <= 10^{4}

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