Use a while loop to repeatedly take input from the user and calculate a sum. The user will only be allowed to type in numbers, but remember the input function returns strings (so you will need to convert them with the built-in int function). If the user inputs the value - 999, then the program should stop and print out the sum of all the numbers entered.

Answer and Explanation:

#take input from user

n = int (input ("Enter any number: "))

#sum variable to store sum

sum=0

#condition to exit from loop

while n!=-999:

#adding entered number in sum variable

sum=sum+n

#take input from user

n = int (input ("Enter any number : "))

#print the sum

print ("sum = ", sum)

output:

Enter any number: 10

Enter any number : 100

Enter any number : - 999

sum = 110