function shop(inputData) {

  let budget = Number(inputData.shift());
  let nameOfProduct = inputData.shift();

  let curProduct = 0;
  let allPrice = 0;

  while (nameOfProduct !== 'Stop') {
    let priceOfProduct = Number(inputData.shift());

    if ((curProduct + 1) % 3 === 0) {
      priceOfProduct = priceOfProduct / 2;
    }

    budget -= priceOfProduct;
    if (budget < 0) {
      break;
    }

    curProduct++;
    allPrice += priceOfProduct;
    nameOfProduct = inputData.shift();
  }

  if (budget >= 0) {
    console.log(`You bought ${curProduct} products for ${(allPrice).toFixed(2)} leva.`);
  } else if (budget < 0) {
    console.log(`You don't have enough money!`);
    console.log(`You need ${Math.abs(budget).toFixed(2)} leva!`);
  }
}