CODE EXAMPLE FOR JAVASCRIPT

.indexof()

// Random Quotes.
const Quotes = [
  "The purpose of our lives is to be happy.",
  "Life is what happens when you're busy making other plans.",
  "Get busy living or get busy dying.",
  "You only live once, but if you do it right, once is enough.",
  "Many of life's failures are people who did not realize how close they were to success when they gave up.",
  "If you want to live a happy life, tie it to a goal, not to people or things.",
  "Never let the fear of striking out keep you from playing the game.",
  "Money and success don't change people; they merely amplify what is already there."];
var num = Quotes.length;
let Dayof = Math.floor(Math.random() * num); //Randome Number Generated With Random Function.
QuoteofDay = Quotes[Dayof];
console.log("Quote Of The Day :", QuoteofDay);
console.log(": You Wont To Enter A New Quote :");
let Yn = prompt("Enter Y Or N To Cancel :");
const Y = "y";
if (Y == Yn) {
  let newQuotes = prompt("Enter New Quotes to Add :");
  Quotes.push(newQuotes); // .push() Method Used To Add New Value In A Array.
  let check = Quotes.indexOf(newQuotes); //.indexof() is used To Check Possition Off Entered Value.
  if (newQuotes == "") {
    console.log(": Blank Value Is Not Allowed :");
    console.log(": To Enter Agen Refresh The Page :");
  }
  else if (newQuotes == Quotes[check]) {
    console.log(" You Entered Quote Is :", newQuotes);
    console.log(": New Quote Updated Sucessfully :");
  }
  else {
    console.log(": Error 404! Refresh And Tray Agen  :");
  }
}
else {
  console.log(" : Thak You !:")
}