class Storage

class Storage {
  constructor(capacity) {
    this.capacity = capacity;
    this.products = [];
  }

  addProduct(product) {
    this.products.push(product);
    this.capacity -= product.quantity;
  }

  getProducts() {
    return this.products.map(x => JSON.stringify(x)).join('\n');
  }

  get totalCost() {
    return this.products.reduce((x, product) => x + product.price * product.quantity, 0);
  }
}