Represented a positive integer number as a sum of multiple positive integer numbers.

A positive integer number N can be represented as a
sum of K positive integer numbers.
i.e, N = n1 + n2 + ... + nk
E.g. 1: 6(N) can be represented as a sum of 2(K) numbers in following way: (1+5), (2+4), (3+3).
E.g. 2: 8(N) can be represented as a sum of 3(K) numbers in following way: (1+1+6), (1+2+5), (1+3+4), (2+2+4), (2+3+3).
To run this function, sample input:
N_as_sum_of_K_numbers(8,3)
Points to remember:
1. N, K both should be positive integer
2. do not give more than two inputs, it will give wrong or no result