//  Whilesum.swift  Copyright (c) Kari Laitinen

//  http://www.naturalprogramming.com

//  2014-09-26  File created.
//  2015-10-17  Last modification.

import Foundation

var  integer_from_keyboard  =  -1
var  sum_of_integers        =   0

print( "\n This program calculates the sum of the integers"
     + "\n you type in from the keyboard. By entering a"
     + "\n zero you can terminate the program. \n" )

while  integer_from_keyboard  !=  0 
{
   print(  String( format: "  Current sum: %8d    Enter an integer: ",
                    sum_of_integers  ), terminator: "" )

   integer_from_keyboard = Int( readLine()! )!

   sum_of_integers  =  sum_of_integers + integer_from_keyboard
}

print( "\n" )


/* Compile and run this program in Terminal window with the command

     xcrun swift Whilesum.swift

*/