Addition and Subtraction of Two Numbers Using Polymorphism in JavaScript

 

Program Listing

const readline = require('readline');

class MathOperation {

    performOperation(a, b) {

        return 0; // Base class default implementation

    }

}

class Addition extends MathOperation {

    performOperation(a, b) {

        return a + b;

    }

}

class Subtraction extends MathOperation {

    performOperation(a, b) {

        return a - b;

    }

}

const rl = readline.createInterface({

    input: process.stdin,

    output: process.stdout

});

rl.question("\n\tEnter the first number: ", (num1) => {

    rl.question("\tEnter the second number: ", (num2) => {

        rl.question("\tEnter the operation (+ for addition, - for subtraction): ", (op) => {

            let operation;

            if (op === '+') {

                operation = new Addition();

            } else if (op === '-') {

                operation = new Subtraction();

            } else {

                console.log("\tInvalid operation.");

                rl.close();

                process.exit();

            }

            const result = operation.performOperation(parseInt(num1), parseInt(num2));

            console.log("\n\tThe Result:", result);

            rl.close();

            console.log("\n\tEnd of Program. Thank you for using this program.\n");

        });

    });

});