Given a large number N, write a program to count the ways to break it into three whole numbers such that they sum up to the original number.
Example 1:
Input: N = 3
Output: 10
Explaination: The ways are
0 + 0 + 3 = 3
0 + 3 + 0 = 3
3 + 0 + 0 = 3
0 + 1 + 2 = 3
0 + 2 + 1 = 3
1 + 0 + 2 = 3
1 + 2 + 0 = 3
2 + 0 + 1 = 3
2 + 1 + 0 = 3
1 + 1 + 1 = 3
Example 2:
Input: N = 1
Output: 3
Explaination: The ways are:
1 + 0 + 0 = 1
0 + 1 + 0 = 1
0 + 0 + 1 = 1
Your Task:
You do not need to read input or print anything. Your task is to complete the function countWays() which takes N as input parameter and returns the total number of possible ways to break N in three whole numbers.
Expected Time Complexity: O(1)
Expected Auxiliary Space: O(1)
Constraints:
1 ≤ N ≤ 10^{9}

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