You are given a positive integer N and you have to find the number of non negative integral solutions to a+b+c=N.

Example 1:
Input:
N = 10
Output:
66
Explanation:
There are 66 possible solutions.
Example 2:
Input:
N = 20
Output:
231
Explanation:
There are 231 possible solutions.

Your Task:
You don't need to read input or print anything. Your task is to complete the function noOfIntSols() which takes an Integer N as input and returns the number of integer solutions possible.

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

Constraints:
1 <= N <= 10^{9}

见题面

见题面