def factorial(n):
if n == 0 or n == 1:
return 1
else:
return n * factorial(n - 1)
num = int(input("Enter a number: "))
if num < 0:
print("Factorial is not defined for negative numbers.")
else:
print(f"The factorial of {num} is {factorial(num)}.")
#source code --> clcoding.com