编写一个类Calculator,有两个属性num1,num2,这两个数据的值，不能在定义的同时初始化，最后实现加减乘 除四种运算.

编写一个类Calculator,有两个属性num1,num2,这两个数据的值，不能在定义的同时初始化，最后实现加减乘除四种运算.

class Calculator {
    private int num1;
    private int num2;

    public int add(){//加法
        return num1+num2;
    }
    public int chengfa(){//乘法
        return num1*num2;
    }
    public double chufa(){//除法
        return num1/num2;
    }
    public int jianfa(){//减法
        return num1-num2;
    }



    public void setNum1(int num1) {
        this.num1 = num1;
    }



    public void setNum2(int num2) {
        this.num2 = num2;
    }
}


public class Test2 {
    public static void main(String[] args) {
        Calculator calculator=new Calculator();
        calculator.setNum2(3);
        calculator.setNum1(2);
        System.out.println(calculator.add());
        System.out.println(calculator.jianfa());
        System.out.println(calculator.chengfa());
        System.out.println(calculator.chufa());
    }

}