Given a positive integer N, the task is to find the number of different ways in which N can be written as a sum of two or more positive integers.
Example 1:
Input:
N = 5
Output: 6
Explanation:
1+1+1+1+1
1+1+1+2
1+1+3
1+4
2+1+2
2+3
So, a total of 6 ways.
Example 2:
Input:
N = 3
Output: 2
Your Task:
Your task is to complete the function countWays() which takes 1 argument(N) and returns the answer%(10^9 + 7).
Expected Time Complexity: O(N^{2})
Expected Auxiliary Space: O(N)
Constraints:
1 <= N <= 10^{3}

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