Consider a N x N grid with indexes of top left corner as (0, 0). Dyck path is a staircase walk from bottom left, i.e., (N-1, 0) to top right, i.e., (0, N-1) that lies above the diagonal cells (or cells on line from bottom left to top right).
The task is to count the number of Dyck Paths from (N-1, 0) to (0, N-1).
Here are the some of the possible paths for different N.

Example 1:
Input:
N = 4
Output:
14
Explanation:
Refer to the diagram above.
Example 2:
Input:
N = 3
Output:
5
Explanation:
Refer to the diagram above.

Your Task:
You don't need to read input or print anything. Your task is to complete the function dyckPaths() which takes an Integer N as input and returns the answer.

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

Constraints:
1 <= N <= 30

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