Given a positive integer N denoting the length of a stick, return the number of ways to split a stick into four parts so that it's possible to form a rectangle using these parts, but is impossible to form a square.
Example 1:
Input: N = 10
Output: 2
Explanation: The 2 ways to split
the stick are {1,1,4,4} , {2,2,3,3}
​Example 2:
Input: n = 20
Output: 4
Explanation: The 4 ways to split
the stick are {1,1,9,9} , {2,2,8,8},
{3,3,7,7} and {4,4,6,6}. Note that
{5,5,5,5} forms square so it is not
considered.
Your Task:
You don't need to read input or print anything. Your task is to complete the function count() which takes N as input and returns the answer.
Expected Time Complexity: O(1)
Expected Auxiliary Space: O(1)
Constraints:
1 ≤ N ≤ 10^{9}

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