human
Number of n | Returns factorial of n.
returns nCr.
Driver code"
Solution in Python:
assistant
#Here is code to number of n and the other steps required.
 def fact ( n ) :
	res = 1
	for i in range ( 2 , n + 1 ) :
		res = res * i
	return res
def nCr ( n , r ) :
	return fact ( n ) // ( ( fact ( r ) * fact ( n - r ) ) )
n = 2
print ( " Number ▁ of ▁ Non - Decreasing ▁ digits : ▁ " , nCr ( n + 9 , 9 ) )