- Write a JavaScript program to display the current day and time in the following format.
Sample Output : Today is : Tuesday. Current time is : 10 PM : 30 : 38
Solution
const today = new Date();
//Get Weekday, it will return number 0 mean Sunday and 6 mean saturday.
const day = today.getDay();
//Weekday array
const weekdays = ["Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Firday", 'Saturday'];
//Get Hour, Minutes and Second from date;
let hours = today.getUTCHours();
let minutes = today.getUTCMinutes();
let seconds = today.getUTCSeconds();
//Find AM and PM from hours
const prepand = ( hours >= 12) ? "PM" : "AM";
//Convert 24 hours to 12 hours format
hours = (hours >= 12) ? hours-12
: hours
// Special Case When Hour is Zero
if(hours === 0 && prepand === 'PM') {
if(minutes == 0 && seconds == 0) {
hours = 12;
prepand = 'Noon'
} else{
hours = 12;
prepand = "PM"
}
}
//Special Case When hour is Zero
if(hours === 0 && prepand === 'AM') {
if(minutes === 0 && seconds === 0) {
hours = 12;
prepand = "Midnight"
} else{
hours = 12;
prepand = 'AM'
}
}
console.log("Today is:", weekdays[day])
console.log("Current Time: " + hours + prepand + " : " + minutes + " : " + seconds);
- Write a JavaScript program to print the current window contents.
Solution
function printCurrentWindowContent(){
window.print();
- Write a JavaScript program to get the current date. Expected Output : mm-dd-yyyy, mm/dd/yyyy or dd-mm-yyyy, dd/mm/yyyy
Solution
//Function to formate Date
function formatDate(date){
const day = date.getDate();
const month = date.getMonth()+1;
const year = date.getFullYear();
if(month < 10) {
month = '0' + month
}
if(day < 10) {
day = '0' + day;
}
console.log(day + "/" + "/" + month + "/" + year)
}
const date = new Date();
formatDate(date)
- Write a JavaScript program to find the area of a triangle where three sides are 5, 6, 7.
Solution
function findTriangleArea(a, b, c){
//Calculate semi perimeter
const semiPerimeter = (a + b + c) / 2;
const area = Math.sqrt(semiPerimeter * ((semiPerimeter - a) * (semiPerimeter - b) * (semiPerimeter - c)))
console.log(area)
}
findTriangleArea(5,6,7)
- Write a JavaScript program to rotate the string 'w3resource' in the right direction. This is done by periodically removing one letter from the string end and attaching it to the front.
Solution
<body onload="animateText('target')">
<h2 id="target">W3Resource</h2>
</body>
function animateText(id) {
let element = document.getElementById(id);
let textNode = element.childNodes[0];
let text = textNode.data;
setInterval(function () {
text = text[text.length - 1] + text.substring(0, text.length - 1);
textNode.data = text;
}, 100);
}
- Write a JavaScript program to determine whether a given year is a leap year in the Gregorian calendar.
Solution
function findLeapYear(year) {
// Return true if the year is divisible by 4 but not divisible by 100 unless it's also divisible by 400
return year % 100 === 0 ? year % 400 === 0 : year % 4 === 0;
}
- Write a JavaScript program to find out if 1st January will be a Sunday between 2014 and 2050.
Solution
for(let year = 2014; year <= 2050; year++) {
date = new Date(year, 0, 1);
if(date.getDay() === 0) {
console.log("1st Jan is being a Sunday " + year)
}
}
- Write a JavaScript program where the program takes a random integer between 1 and 10, and the user is then prompted to input a guess number. The program displays a message "Good Work" if the input matches the guess number otherwise "Not matched".
Solution
let number = Math.ceil(Math.random() * 10);
let userInput = prompt("Enter number between 1 - 10");
if(userInput == number){
console.log("Good Work")
} else{
console.log("Match Not Found")
}
- Write a JavaScript program to calculate the days left before Christmas.
const today = new Date();
const christmasDay = new Date(today.getFullYear(), 11, 25);
let oneday = 1000 * 60 * 60 * 24;
if(today.getMonth() == 11 && today.getDate() > 25) {
christmasDay.setFullYear(christmasDay.getFullYear()+1)
}
let dayLeft = Math.ceil((christmasDay - today) / oneday);
console.log(dayLeft)
- Write a JavaScript program to calculate multiplication and division of two numbers (input from the user).
Solution: We can perform same task with html form as well.
const userInput1 = prompt("Enter first number");
const userInput2 = prompt("Enter second number");
const operation = prompt("Enter operation operator");
if(operation === "*"){
const result = parseInt(userInput1) * parseInt(userInput2);
console.log("Multiple of two number " + result)
}
if(operation === "/"){
const result = parseInt(userInput1) / parseInt(userInput2);
console.log("Division of two number " + result)
}
- Write a JavaScript exercise to get the filename extension.
const fileName = "myresume.docx";
//this method will remove "." and result filename and extension in an array;
const getFileExtension = fileName.split(".")
//Using pop method remove last element from an array;
console.log(getFileExtension.pop())
- Write a JavaScript program to get the difference between a given number and 13, if the number is broader than 13 return double the absolute difference.
Solution
function findDifferences(number) {
if(number > 13) {
let result = (number - 13) * 2;
return result;
} else{
let result = 13 - number;
return result;
}
}
console.log(findDifferences(32))
- Write a JavaScript program to compute the sum of the two given integers. If the two values are the same, then return triple their sum.
Solution
function getSum(number1, number2) {
if(number1 === number2){
return ((number1 + number2) * 3);
} else{
return (number1 + number2);
}
}
console.log(getSum(5, 5));
- Write a JavaScript program to check a pair of numbers and return true if one of the numbers is 50 or if their sum is 50.
Solution
function checkNumbersPair(num_1, num_2){
let sumTwoNumbers = num_1 + num_2;
if(num_1 === 50 || num_2 === 50 || sumTwoNumbers === 50) {
return true;
} else{
return false;
}
}
console.log(checkNumbersPair(45, 6))
- Write a JavaScript program to check two given integers whether one is positive and another one is negative.
Solution
function positive_negative(a, b) {
if ((a > 0 && b < 0) || (a < 0 && b > 0)) {
return true;
} else {
return false;
}
}
positive_negative(2, 2);
- Write a JavaScript program to create another string by adding "Py" in front of a given string. If the given string begins with "Py" return the original string.
Solution
function modifyString(str) {
if (str === null || str === undefined || str.substring(0, 2) === "Py") {
return str;
} else {
return "Py" + str;
}
}
console.log(modifyString("Py"));
- Write a JavaScript program to remove a character at the specified position in a given string and return the modified string.
Solution
function removeCharacter(str, index) {
let firstStep = str.substring(0, index);
let lastStep = str.substring(index + 1, str.length);
return firstStep + lastStep;
}
console.log(removeCharacter("AjitSharma", 3));
- Write a JavaScript program to create a new string from a given string by changing the position of the first and last characters. The string length must be broader than or equal to 1.
Solution
function createNewString(str) {
if (str.length <= 1) {
return str;
}
let firstChar = str.substring(0, 1);
let lastChar = str.substring(str.length - 1, str.length);
let midCharacters = str.substring(1, str.length - 1);
return lastChar + midCharacters + firstChar;
}
console.log(createNewString("tjiA"));
- Write a JavaScript program to check whether a given positive number is a multiple of 3 or 7.
Solution:
function checkNumber(number) {
if (number % 3 === 0 || number % 7 === 0) {
return true;
} else {
return false;
}
}
console.log(checkNumber(53));
- Write a JavaScript program to create a string from a given string. This is done by taking the last 3 characters and adding them at both the front and back. The string length must be 3 or more.
Solution
function generateString(str) {
if (str.length < 3) {
return str;
} else {
let last3Char = str.substring(str.length - 3, str.length);
let midChar = str.substring(0, str.length - 3);
console.log(midChar);
let result = last3Char + midChar + last3Char;
return result;
}
}
console.log(generateString("Aji"));
- Write a JavaScript program to check whether a string starts with 'Java' if it does not otherwise.
function checkString(str) {
if (str.length <= 4) {
return false;
}
let front = str.substring(0, 4);
if (front === "Java") {
return true;
} else {
return false;
}
}
console.log(checkString("Jasvascript"));
- Write a JavaScript program to find the largest of three given integers.
function findLargetNumber(a, b, c) {
return Math.max(a, b, c);
}
console.log(findLargetNumber(-5, -1, 5));
- Write a JavaScript program to find the closest value to 100 from two numerical values.
function findClosestToHundred(a, b) {
if (a != b) {
//Calculate the absolute difference betwen a - 100
const firstAbsNo = Math.abs(a - 100);
//Calculate the absolute difference between b - 100
const secondAbsNo = Math.abs(b - 100);
if (firstAbsNo < secondAbsNo) {
return a;
} else {
return b;
}
} else {
return "Given both number is at the same distance from 100";
}
}
console.log(findClosestToHundred(99, 99));
- Write a program to check whether a specified character exists between the 2nd and 4th positions in a given string.
function checkCharacter(str, c) {
const range = str.substring(1, 4);
return range.includes(c);
}
console.log(checkCharacter("javascript", "v"));
- Write a JavaScript program to produce a new string that has the first 3 characters in lower case from a given string. If the string length is less than 3 convert all the characters to upper case.
function camelCase(str) {
if (str.length < 3) {
return str.toUpperCase();
}
const lowerCase = str.substring(0, 3).toLowerCase();
const secondPart = str.substring(3, str.length);
return lowerCase + secondPart;
}
console.log(camelCase("FULLSTACK"));
- Write a JavaScript program to capitalize the first letter of each word in a given string.
function capitalizeEachWord(str) {
str = str.split(" ");
for (let i = 0; i < str.length; i++) {
str[i] = str[i][0].toUpperCase() + str[i].substr(1);
}
return str.join(" ");
}
console.log(capitalizeEachWord("i ajit sharma and i am frontend developer"));
- Write a JavaScript program to convert letters of a given string alphabetically.
function convertLetters(letters) {
return letters.split("").sort().join("");
}
console.log(convertLetters("javascript"));
- Write a JavaScript program to check whether the characters a and b are separated by exactly 3 places anywhere (at least once) in a given string.
function checkCharacters(str) {
return /a...b/.test(str) || /b...a/.test(str);
}
console.log(checkCharacters("Chainsbreak"));