#Using the Python language, have the function FirstFactorial(num) take the num parameter being passed and return the factorial of it (ie. if num = 4, return (4 * 3 * 2 * 1)). For the test cases, the range will be between 1 and 18.

#Use the Parameter Testing feature in the box below to test your code with different arguments.


def FirstFactorial(num): 
    
    factorial = 1
    if num == 0:
        print (1)
    else:
        for i in range(1,num+1):
            factorial = factorial * i
    print (factorial)
       
# keep this function call here  
# to see how to enter arguments in Python scroll down

FirstFactorial(int(input()))
