.
Answer:
// program in Python to check perfect number
#function to find number is perfect or not
def is_Perfect_Number(n):
#total variable
tot = 1
i = 2
#sum of all divisor of number
while i*i<=n:
if n%i==0:
tot = tot + i + n/i
if tot == n and n != 1:
return 1
i = i+1
return 0
#read until user enter a perfect number
while True:
#read integer
num = int(input("Input an integer: "))
#call the function
if(is_Perfect_Number(num)):
print(num,"is perfect number")
#if perfect number break
break
else:
print(num,"is not a perfect number")
#ask again
print("try again.")
Explanation:
Read number from user and then call the function is_Perfect_Number() with parameter "num".This will find the sum of all divisor of number.If sum is equal to number then it will return 1 else return 0.If the number is not perfect then it will again ask to enter a number until user enter a perfect number.
Output:
Input an integer: 24
24 is not a perfect number
try again.
Input an integer: 28
28 is perfect number
Answer: There are many different types of user interfaces. To decide on the user interface depends entirely on the requirement of the client.
Explanation:
There are different types of interfaces such as command line user interface, graphical user interface, menu based, form based. Therefore to choose among them it depend on the requirement specified by a client. Mostly nowadays GUI is used. to maintain records form based is preferred. For system software CUI is better due to decrease its pressure on the processor. Networking is also both GUI and CUI. So it depend mainly on the type of application developed , client requirements, power consumption based on its dependence on processor power.
