begin{subfigure}[t]{.49\textwidth}
    	\centering
	\begin{tikzpicture}
		\draw 	(1,0)--(1,2)
				(1.5,0)--(1.5,2)
				(2,0)--(2,2)
				(4,0)--(4,2);
		\draw 	(1,0) node[label=below:{1}] {} 
				(1.5,0)node[label=below:{1}] {} 
				(2,0)node[label=below:{1}] {} 
				(4,0)node[label=below:{1}] {} ;
		\draw 	(2.5,1) node[cross] {}
				(3,1) node[cross] {}
				(3.5,1) node[cross] {}
				(4.5,1) node[cross] {};
		\draw 	(2.5,1) node[label=above:{3}] {}
				(3,1) node[label=above:{3}] {}
				(3.5,1) node[label=above:{3}] {}
				(4.5,1) node[label=above:{3}] {};
		\draw [dotted] (1,1)--(1.5,1)
				(2,1)--(4,1);
		\draw	(4,1)--(4.5,1);
		\draw 	(2,.2)--(4,.2)
				(2,1.8)--(4,1.8)
				(1.5,.5)--(2,.5)
				(1.5,1.5)--(2,1.5);
	\end{tikzpicture}
        \caption{}
    	\end{subfigure}
	\hfill
    	\begin{subfigure}[t]{.49\textwidth}
    	\centering
	\begin{tikzpicture}
		\draw 	(1,0)--(1,2)
				(1.5,0)--(1.5,2)
				(2,0)--(2,2)
				(3.5,0)--(3.5,2);
		\draw 	(1,0) node[label=below:{1}] {} 
				(1.5,0)node[label=below:{1}] {} 
				(2,0)node[label=below:{1}] {} 
				(3.5,0)node[label=below:{1}] {} ;
		\draw 	(2.5,1) node[cross] {}
				(3,1) node[cross] {}
				(4,1) node[cross] {}
				(4.5,1) node[cross] {};
		\draw 	(2.5,1) node[label=above:{3}] {}
				(3,1) node[label=above:{3}] {}
				(4,1) node[label=above:{3}] {}
				(4.5,1) node[label=above:{3}] {};
		\draw [dotted] (1,1)--(1.5,1)
				(2,1)--(3.5,1);
		\draw	(4,1)--(4.5,1);
		\draw	(3.5,1.05)--(3.95,1.05)
				(3.5,.95)--(3.95,.95);
		\draw 	(2,.2)--(3.5,.2)
				(2,1.8)--(3.5,1.8)
				(1.5,.5)--(2,.5)
				(1.5,1.5)--(2,1.5);
	\end{tikzpicture}
        \caption{}
    	\end{subfigure}
    	\hfill
    	\begin{subfigure}[t]{.49\textwidth}
    	\centering
	\begin{tikzpicture}
		\draw 	(1,0)--(1,2)
				(1.5,0)--(1.5,2)
				(2.5,0)--(2.5,2)
				(3.5,0)--(3.5,2);
		\draw 	(1,0) node[label=below:{1}] {} 
				(1.5,0)node[label=below:{1}] {} 
				(2.5,0)node[label=below:{1}] {} 
				(3.5,0)node[label=below:{1}] {} ;
		\draw 	(2,1) node[cross] {}
				(3,1) node[cross] {}
				(4,1) node[cross] {}
				(4.5,1) node[cross] {};
		\draw 	(2,1) node[label=above:{3}] {}
				(3,1) node[label=above:{3}] {}
				(4,1) node[label=above:{3}] {}
				(4.5,1) node[label=above:{3}] {};
		\draw [dotted] (1,1)--(1.5,1)
				(2.5,1)--(3.5,1);
		\draw	(4,1)--(4.5,1)
				(2,1)--(2.5,1);
		\draw	(3.5,1.05)--(3.95,1.05)
				(3.5,.95)--(3.95,.95);
		\draw 	(2.5,.2)--(3.5,.2)
				(2.5,1.8)--(3.5,1.8)
				(1.5,.3)--(2.5,.3)
				(1.5,1.7)--(2.5,1.7);
	\end{tikzpicture}
        \caption{}
    	\end{subfigure}
    	\hfill
    	\begin{subfigure}[t]{.49\textwidth}
    	\centering
	\begin{tikzpicture}
		\draw 	(1,0)--(1,2)
				(2,0)--(2,2)
				(2.5,0)--(2.5,2)
				(3.5,0)--(3.5,2);
		\draw 	(1,0) node[label=below:{1}] {} 
				(2,0)node[label=below:{1}] {} 
				(2.5,0)node[label=below:{1}] {} 
				(3.5,0)node[label=below:{1}] {} ;
		\draw 	(1.5,1) node[cross] {}
				(3,1) node[cross] {}
				(4,1) node[cross] {}
				(4.5,1) node[cross] {};
		\draw 	(1.5,1) node[label=above:{3}] {}
				(3,1) node[label=above:{3}] {}
				(4,1) node[label=above:{3}] {}
				(4.5,1) node[label=above:{3}] {};
		\draw [dotted] (1,1)--(2,1)
				(2.5,1)--(3.5,1);
		\draw	(4,1)--(4.5,1)
				(2,1)--(2.5,1);
		\draw	(3.5,1.05)--(3.95,1.05)
				(3.5,.95)--(3.95,.95)
				(2,1.05)--(1.55,1.05)
				(2,.95)--(1.55,.95);
		\draw 	(2.5,.2)--(3.5,.2)
				(2.5,1.8)--(3.5,1.8)
				(2,.3)--(2.5,.3)
				(2,1.7)--(2.5,1.7);
	\end{tikzpicture}
        \caption{}
    	\end{subfigure}
    	\hfill
    	\begin{subfigure}[t]{.49\textwidth}
    	\centering
	\begin{tikzpicture}
		\draw 	(1,0)--(1,2)
				(2,0)--(2,2)
				(2.5,0)--(2.5,2)
				(3.5,0)--(3.5,2);
		\draw 	(1,0) node[label=below:{1}] {} 
				(2,0)node[label=below