function tf = check( p )
	s = size(p);
	s = s(1);

	if( s <= 1 )
		tf = true;
		return;
	end

	if( s == 2 )
		if ( p(1, 1) == p(2, 4) )
			tf = true;
		else
			tf = false;
		end
		return;
	end

	if( s == 3 )
		if ( p(1, 1) == p(2, 4) && p(1, 2) == p(3, 5) && p(2, 3) == p(3, 6) )
			tf = true;
		else
			tf = false;
		end
		return;
	end

	if( s == 4 )
		if ( p(1, 1) == p(2, 4) && p(1, 2) == p(3, 5) && p(2, 3) == p(3, 6) && p(1, 3) == p(4, 6) && p(3, 4) == p(4, 1))
			tf = true;
		else
			tf = false;
		end
		return;
	end

	if( s == 5 )
		if ( p(1, 1) == p(2, 4) && p(1, 2) == p(3, 5) && p(2, 3) == p(3, 6) && p(1, 3) == p(4, 6) && p(3, 4) == p(4, 1) && p(1, 4) == p(5, 1) && p(4, 5) == p(5, 2))
			tf = true;
		else
			tf = false;
		end
		return;
	end

	if( s == 6 )
		if ( p(1, 1) == p(2, 4) && p(1, 2) == p(3, 5) && p(2, 3) == p(3, 6) && p(1, 3) == p(4, 6) && p(3, 4) == p(4, 1) && p(1, 4) == p(5, 1) && p(4, 5) == p(5, 2) && p(1, 5) == p(6, 2) && p(5, 6) == p(6, 3))
			tf = true;
		else
			tf = false;
		end
		return;
	end

	if( s == 7 )
		if ( p(1, 1) == p(2, 4) && p(1, 2) == p(3, 5) && p(2, 3) == p(3, 6) && p(1, 3) == p(4, 6) && p(3, 4) == p(4, 1) && p(1, 4) == p(5, 1) && p(4, 5) == p(5, 2) && p(1, 5) == p(6, 2) && p(5, 6) == p(6, 3) && p(1, 6) == p(7, 3) && p(6, 1) == p(7, 4) && p(7, 2) == p(2, 5))
			tf = true;
		else
			tf = false;
		end
		return;
	end
end