#include <bits/stdc++.h>
using namespace std;

char c[15];
int main()
{
	int i=1;
	int f;
	while (cin >> c[i])
	{
		if (c[i] >= 'A' && c[i] <= 'Z')
			f++;
		if (c[i] >= 'a' && c[i] <= 'z')
			f++;
		if (c[i] >= '0' && c[i] <= '9')
			f++;
		if (c[i] == '!' || c[i] == '@' || c[i] == '#' || c[i] == '$')
			f++;
		i++;
		if (c[i-1] == ',')	
		{
			if (f >= 3 && i-2 >= 6 && i-2 <= 12)
			{
				for (int j=1; j<i-1; j++)
					cout << c[j];
				cout << endl;
			}
			i = 1;
		} 
	}
	return 0;
}

(>^ω^<)拜托大佬看一眼啊