Exam shopping - Dictionaries

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Exam_shopping
{
    class Program
    {
        static void Main(string[] args)
        {
            Dictionary<string, int> dict = new Dictionary<string, int>();
            string stock = Console.ReadLine();
            while (stock != "shopping time")
            {
                string[] stockAdd = stock.Split(' ').ToArray();
                string stockItem = stockAdd[1];
                int stockItemQuantity = int.Parse(stockAdd[2]);
                if (!dict.ContainsKey(stockItem))
                {
                    dict[stockItem] = stockItemQuantity;
                }
                else
                {
                    dict[stockItem] += stockItemQuantity;
                }
                stock = Console.ReadLine();
            }
            string buy = Console.ReadLine();
            while (buy != "exam time")
            {
                string[] buying = buy.Split(' ').ToArray();
                string buyItem = buying[1];
                int buyItemQuantity = int.Parse(buying[2]);
                if (!dict.ContainsKey(buyItem))
                {
                    Console.WriteLine($"{buyItem} doesn't exist");
                }
                else
                {
                    if (dict[buyItem] == 0)
                    {
                        Console.WriteLine($"{buyItem} out of stock");
                    }
                    else if (buyItemQuantity >= dict[buyItem])
                    {
                        dict[buyItem] = 0;
                    }
                    else
                    {
                        dict[buyItem] -= buyItemQuantity;
                    }
                }
                buy = Console.ReadLine();
            }

            foreach (KeyValuePair<string, int> item in dict)
            {
                if (item.Value > 0)
                {
                    Console.WriteLine($"{item.Key} -> {item.Value}");
                }
            }
        }
    }
}