C++ :

#include<iostream>
using namespace std;
int main()
{
	for (int a=0; a<=1; a++)
		for (int b=0; b<=1; b++)
			for (int c=0; c<=1; c++)
				for (int d=0; d<=1; d++)
					for (int e=0; e<=1; e++)
						for (int f=0; f<=1; f++)
							if (a+b>=1 && a+d!=2 && a+e+f==2 && (b+c==0||b+c==2)
								&& c+d==1 && (d+e==0||d==1))
							{
								if (a==1) cout<<"A,";
								if (b==1) cout<<"B,";
								if (c==1) cout<<"C,";
								if (d==1) cout<<"D,";
								if (e==1) cout<<"E,";
								if (f==1) cout<<"F,";
								cout<<endl;
							}
	return 0;
}