The superclass Calculator contains: a (protected) double instance variable , accumulator, that contains the current value of the calculator.

LANGUAGE: JAVA

CHALLENGE:

The superclass Calculator contains:
a (protected) double instance variable , accumulator, that contains the current value of the calculator.
write a subclass, CalculatorWithMemory, that contains:
a double instance variable , memory, initialized to 0
a method , save, that assigns the value of accumulator to memory
a method , recall, that assigns the value of memory to accumulator
a method , clearMemory, that assigns zero to memory
a method , getMemory, that returns the value stored in memory

SOLUTION:

public class CalculatorWithMemory extends Calculator {
    public void save() {
        memory = accumulator;
    }
    public void recall() {
        accumulator = memory;
    }
    public void clearMemory() {
        memory = 0;
    }
    public double getMemory() {
        return memory;
    }
    private double memory;
}

Posted in , ,