using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
class Program
{
static void Main(string[] args)
{
List<int> list = new List<int>();
string x;
while (((x = Console.ReadLine())) != null)
{
char sign = char.Parse(x);
switch (sign)
{
case '+':
{
if (list.Count >= 10) Console.WriteLine(":(");
else
{
int number = int.Parse(Console.ReadLine());
list.Add(number);
Console.WriteLine(":)");
}
break;
}
case '-':
{
if (list.Count == 0) Console.WriteLine(":(");
else
{
Console.WriteLine(list[list.Count - 1]);
list.Remove(list[list.Count - 1]);
}
break;
}
}
}
}
}
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