Shariar-Hasan

function isPrime(num)
{
    for (var i = 2; i<num ; i++)
    {
        if(num%i == 0)
        {
            return num+" is not a prime number";
        }
    }
    return num+" in a prime number";

Shariar-Hasan

// if you want whole fibonacci series till n
let fibb = [0, 1];
function fibonacciTillN(n) {
  if (fibb[n - 1] != undefined) {
    return fibb[n - 1];
  } else {
    return (fibb[n - 1] = fibonacciTillN(n - 1) + fibonacciTillN(n - 2));
  }
}
fibonacciTillN(10);

Shariar-Hasan

// if you want the whole series of fibonacci

var fib = [0, 1];
var n = 10;    // you can change this value
if (n == 1 || n == 2) {
    console.log(fib);
}
else {
    for (var i = 2; i < n; i++) {
        fib.push(fib[i-1]+fib[i-2]);

Shariar-Hasan

var numbers = [1,2,5,3,7,5,6,8,9,9,0,3,4,5,6,5,5,4,3,3,4,4];

function duplicateRemover(numbers)
{
    var uniqueArray = []
    for(var i = 0; i< numbers.length ; i++)
    {
        if(uniqueArray.indexOf(numbers[i]) == -1)
        {
            uniqueArray.push(numbers[i]);

Shariar-Hasan

// how to swap two variable
//*************** * way -1****************

var a = 5;
var b = 7;

console.log("brfore swap a = ",a,"and b =",b);

Shariar-Hasan

var words = "amake amar moto thakte dao. ami nijeke nijer moto ghuchiye niyechi";
var counter=0;
for (var i = 0; i< words.length ; i++)
{
    if(words[i] == " " && words[i-1] != " " && i != 0 && i != words.length-1)
    {
        counter++;
    }

}

Shariar-Hasan

// using a loop
var str = "i am a javascript programmer";
var reverseString = ""
for(var i = str.length ; i > 0; i--)
{
    reverseString += str[i-1];
}
console.log(reverseString);

Shariar-Hasan

// how to create random numbers
// random numbers

var rand = Math.random();   //will create random number between 0 - 1
console.log(rand);

Shariar-Hasan

let  numbers = [1,2,3,4,5,6,7,8,9,10];


let result1 = numbers.map( (x) => x*10 ); 
console.log(result1);

let result2 = numbers.filter( (x) => x%2 );         //returns all values that meet the condition
console.log(result2);

Shariar-Hasan

// genarate random number with specific digit using function 

function randNumber(n){
    return Math.floor((Math.random()*10**n));       //if you want n digit random number as a number
}
function randNumString(n){
    return (Math.random()*10**n+" ").split('.')[0];       //if you want n digit random number as a string
}