Question

USING PYTHON PLEASE

Write a program that calculates the factorial value of a number entered by the user. Remember that x! =x* (x-1)* (x-2)*... *3+ 2* 1. Your program should check the value input by the user to ensure it is valid (i.e., that it is a number > =1). To do this, consider looking at the is digit() function available in Python. If the user enters an incorrect input, your program should continue to ask them to enter a proper value until they do so, at which point the program can calculate the factorial and print out the result. Save your python program in a file called a2q2.py and add it to your submission zip file.

Answer 1

The desired python program is given below:

fact = 1

#Here we are doing number validation
while True:
    numb = int(input("Enter the number: "))
    if numb < 0:
       print("Factorial for negative number does not exist")
    else:
        break
  
if numb == 0:
    print("The factorial of value 0 is 1")
else:
    for i in range(1,numb + 1):
        fact = fact*i
print("The factorial of",numb,"is",fact)

Ouput Screen

Python 3.5.1 (v3.5.1:37a07cee5969, Dec 6 2015, 01:38:48) [MSC v.1900 32 bit (In tel)] on win32 Type "copyright", "credits" or "license () " for more information. RESTART: C:/Users/eveaash AppData/Local/Programs/Python/Python35-32/factorial_p rogram. py Enter the number-4 Factorial for negative number does not exist Enter the number: 3 The factorial of 3 i3 6 2 4