//******************************
//*?????????
//*????? 1200012858
//*???2012-12-8
//******************************
int main ()
{
	char str[1000] = {0}, str1[1000];
	char *s = str, *s1 = str1;   // *s???????????????????*s1??????????
	cin.getline(str, 1000);
	char b = str[0];             // ?????????
	//for(; s < p; s++)
	while (*(s + 1))             // ?????????
	{
	    *s1 = *s + *++s;     // ?????*s1 = *s + *++s;????????????s??????
		cout << *s1;
		
		s1++;
	}
	*s1 = *s + b;
	cout << *s1 << endl;
	return 0;
}