function printStock(stock, orderedProducts) {
    let currentStock = {};

    stock.forEach(e => {
        let index = stock.indexOf(e);
        if (index % 2 == 0) {
            if (!currentStock[e]) {
                currentStock[e] = Number(stock[index + 1]);
            } else {
                currentStock[e] += Number(stock[index + 1]);
            }
        }
    });

    orderedProducts.forEach(el => {
        let index = orderedProducts.indexOf(el);
        if (index % 2 == 0) {
            if (!currentStock[el]) {
                currentStock[el] = Number(orderedProducts[index + 1]);
            } else {
                currentStock[el] += Number(orderedProducts[index + 1]);
            }
        }
    });

    // for (let i = 0; i < orderedProducts.length; i += 2) {
    //     let element = orderedProducts[i];
    //     if (currentStock[element]) {
    //         currentStock[element] += +orderedProducts[i + 1];
    //     } else {
    //         currentStock[element] = +orderedProducts[i + 1];
    //     }
    // }

    Object.keys(currentStock)
        .forEach(product => console.log(`${product} -> ${currentStock[product]}`));
}