To perform arithmetic operations (APEX)

public class arthematic { 

   

    public Integer num1 { get; set; }

    public Integer num2 { get; set; }

   

    public Integer sum { set; }//If we take inputbox then only we need this, if use outputtext this datamember is not required

   

    public Integer diff { set; }

   

    public Integer mul { set; }

   

    public Integer div { set; }    

  

    public PageReference addition() {

   

        //return null;

        return Page.arthematic;

    }

   

    public arthematic() {

        num1 = num2 = 0;       

    }   

   

   //Addition

    public Integer getSum() {

        //return num1 + num2;       

        return add();

    }   

    public Integer add() {       

        return num1 + num2;

    }

   

    //Subtraction

    public Integer getDiff() {

        //return num1 + num2;       

        return diff();

    }   

    public Integer diff() {       

        return num1 - num2;

    }

   

    //Multiplication

    public Integer getMul() {

        //return num1 + num2;       

        return mul();

    }   

    public Integer mul() {       

        return num1 * num2;

    }

   

    //Division

    public Integer getDiv() {

        //return num1 + num2;       

        return div();

    }   

    public Integer div() {       

        return num1 / num2;

    }/*//<apex:commandButton value="div"/>

//<apex:outputText value="{!div}"/><br></br><br></br>*/ //Getting Exception

   

    }

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VF CODE

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