#include <iostream>
using namespace std;
int main()
{
char znak;
int i=0;
int tablica[12];
while (cin>>znak)
{
//-------------------------------------------------------
if (znak=='+')
{
if (i<0)
i=0;
if (i>=0 && i<10)
{
cin>>tablica[i];
cout<<":)"<<endl;
i++;
}
if (i>=10)
{
cin>>tablica[i];
cout<<":("<<endl;
}
}
//-------------------------------------------------------
if (znak=='-')
{
if (i<=0)
{
cout<<":("<<endl;
}
if (i>0 && i<=10)
{
i--;
cout<<tablica[i]<<endl;
}
}
//-------------------------------------------------------
}
return 0;
}
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