Directions:

Create a simple integer calculator using the MARIE computer.

The program should execute as follows:

Using the INPUT instruction wait for the user to enter a decimal number.

Using the INPUT instruction wait for the user to enter the operator as the ASCII character $+,-$ or $*.$

Using the INPUT instruction wait for the user to enter a second decimal number.

Perform the desired addition, subtraction, or multiplication operation.

Store the result in a variable in memory.

Display the result via the OUTPUT instruction.

If an invalid operation is requested, display a zero as the result.

The code should be clearly commented.

The multiply can be done by repeated additions. For example, $12*3$ would be calculated as $12+12+12.$ You need to support a negative multiplier and negative multiplicand $(12*-3).$