#include <stdio.h> #include using namespace std; int main() { int n; 0 <= n <= 25; cin >> n; if (n>=0 && n<=3) { cout<<"infant"; } else if (n>=4 && n<=12) { cout<<"child";

}
else if (n>=13 && n<=18)
{
	cout<<"youngster";
}
else if (n>=19 && n<=25)
{
	cout<<"youth";
}

}