The problem is to count all the possible paths from top left to bottom right of a MxN matrix with the constraints that from each cell you can either move to right or down.
Example 1:
Input:
M = 3 and N = 3
Output: 6
Explanation:
Let the given input 3*3 matrix is filled
as such:
A B C
D E F
G H I
The possible paths which exists to reach
'I' from 'A' following above conditions
are as follows:ABCFI, ABEHI, ADGHI, ADEFI,
ADEHI, ABEFI

Example 2:
Input:
M = 2 and N = 8
Output: 8
Your Task:
You don't need to read input or print anything. Your task is to complete the function numberOfPaths() which takes the integer M and integer N as input parameters and returns the number of paths..
Expected Time Complexity: O(m + n - 1))
Expected Auxiliary Space: O(1)

Constraints:
1 ≤ M, N ≤ 10

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