def fact(num):
    factorial = 1
    if num < 0:
       print("Sorry, factorial does not exist for negative numbers")
    elif num == 0:
       print("The factorial of 0 is: 1")
    else:
       for i in range(1,num + 1):
           factorial = factorial*i
       print("The factorial of",num,"is:",factorial)
try:
    num = int(input('Enter Number: '))
except:
    print('Enter Integer Numbers')
else:
    fact(num)
