Summator

The program was conceived as a calculator for calculating the cost of the check. Put it in the cart the product and drive its value. The program remembers and outputs the result. Of course, you can count on a ordinary calculator. But, with the usual calculator, it is likely to make a mistake or lose the result in the middle of the list.
The accumulator holds not only stores the sum, but the list of entered numbers. So to be mistaken difficult, and to correct easily.
And the function of simple calculator is present.