জাভাস্ক্রিপ্ট

console.log("Hello World!");

function factorial(n) {if (n===0||n===1) return 1; //fact0=fact1=1
    return n * factorial(n - 1)}

factorial(3); // returns 6

function counter() {
var count = 0;
    return function() {return ++count}};

var closure = counter();
closure(); // returns 1
closure(); // returns 2
closure(); // returns 3

function sum() {var x = 0;
    for (var i = 0; i < arguments.length; ++i) x += arguments[i];
    return x}

sum(1, 2); // returns 3
sum(1, 2, 3); // returns 6

var counter = (function () {
    var i = 0; // private property

    return {   // public methods
        get: function () {
            alert(i);
        },
        set: function (value) {
            i = value;
        },
        increment: function () {
            alert(++i);
        }
    };
})(); // module

counter.get();       // shows 0
counter.set(6);
counter.increment(); // shows 7
counter.increment(); // shows 8

/* Finds the lowest common multiple (LCM) of two numbers */
function LCMCalculator(x, y) { // constructor function
    var checkInt = function (x) { // inner function
        if (x % 1 !== 0) {
            throw new TypeError(x + " is not an integer"); // throw an exception
        }
        return x;
    };
    this.a = checkInt(x)
    //   semicolons   ^^^^  are optional, a newline is enough
    this.b = checkInt(y);
}
// The prototype of object instances created by a constructor is
// that constructor's "prototype" property.
LCMCalculator.prototype = { // object literal
    constructor: LCMCalculator, // when reassigning a prototype, set the constructor property appropriately
    gcd: function () { // method that calculates the greatest common divisor
        // Euclidean algorithm:
        var a = Math.abs(this.a), b = Math.abs(this.b), t;
        if (a < b) {
            // swap variables
            t = b;
            b = a;
            a = t;
        }
        while (b !== 0) {
            t = b;
            b = a % b;
            a = t;
        }
        // Only need to calculate GCD once, so "redefine" this method.
        // (Actually not redefinition—it's defined on the instance itself,
        // so that this.gcd refers to this "redefinition" instead of LCMCalculator.prototype.gcd.
        // Note that this leads to a wrong result if the LCMCalculator object members "a" and/or "b" are altered afterwards.)
        // Also, 'gcd' === "gcd", this['gcd'] === this.gcd
        this['gcd'] = function () {
            return a;
        };
        return a;
    },
    // Object property names can be specified by strings delimited by double (") or single (') quotes.
    lcm : function () {
        // Variable names don't collide with object properties, e.g., |lcm| is not |this.lcm|.
        // not using |this.a*this.b| to avoid FP precision issues
        var lcm = this.a/this.gcd()*this.b;
        // Only need to calculate lcm once, so "redefine" this method.
        this.lcm = function () {
            return lcm;
        };
        return lcm;
    },
    toString: function () {
        return "LCMCalculator: a = " + this.a + ", b = " + this.b;
    }
};

// একটা আউটপুট ফাংশন; এই প্রয়োগ সুধুমাত্র ওয়েব ব্রাওজারে কাজ করবে । 
function output(x) {
    document.body.appendChild(document.createTextNode(x));
    document.body.appendChild(document.createElement('br'));
}

// Note: Array's map() and forEach() are defined in JavaScript 1.6.
// They are used here to demonstrate JavaScript's inherent functional nature.
[[25, 55], [21, 56], [22, 58], [28, 56]].map(function (pair) { // array literal + mapping function
    return new LCMCalculator(pair[0], pair[1]);
}).sort((a, b) => a.lcm() - b.lcm()) // sort with this comparative function; => is a shorthand form of a function, called "arrow function"
  .forEach(printResult);

function printResult(obj) {
    output(obj + ", gcd = " + obj.gcd() + ", lcm = " + obj.lcm());
}