function solve() {
    Array.from(document.querySelectorAll('.add-product')).forEach(x => x.addEventListener('click', addToCart));
    document.querySelector('.checkout').addEventListener('click', checkout);

    const buttons = Array.from(document.querySelectorAll('button'));
    const textArea = document.querySelector('textarea');
    const products = new Set();
    let total = [];

    function addToCart(e) {
       const productName = e.target.parentElement.parentElement.querySelector('.product-title').textContent;
       const productPrice = e.target.parentElement.parentElement.querySelector('.product-line-price').textContent;

       textArea.textContent += `Added ${productName} for ${productPrice} to the cart.\n`

       if (!products.has(productName)) products.add(productName);
       total.push(Number(productPrice));

    }

    function checkout() {
       const totalPrice = total.reduce((acc, x) => acc + x, 0);
       textArea.textContent += `You bought ${Array.from(products).join(', ')} for ${totalPrice.toFixed(2)}.`;

       buttons.forEach(b => b.disabled = true);
    }
 }