\begin{figure*}
    \centering
        \tikzstyle{place}=[circle,draw=blue!50,fill=blue!20,thick,minimum size=10mm]
    \tikzstyle{transition}=[rectangle,draw=black!50,fill=black!20,thick,minimum size=10mm]
        \begin{tikzpicture}[scale=0.6]
            \node[place] (st) at ( 0,29) {$S_i$};
            \node[transition] (as2) at ( 4,25) {$S_{i^'}$};
            \node[transition] (as1) at ( -4,25) {$S_{i^'}$};
            \foreach \y in {1,2}
                \foreach \x in {1,2}
                    \node[place] (s\y\x) at (8*\y+4*\x-18,21) {$S_i$};
    
            \node[circle,draw=black!50,fill=red!60,thick,minimum size=10mm] (sd) at  (-6,21) {$S_j$};
            
            \foreach \y in {1,2}
                \draw [->] (st.south) -- (as\y.north);
            
            \foreach \y in {1,2}
                \foreach \x in {1,2}
                    \draw [->] (as\y.south) -- (s\y\x.north);
    
            
            
            \node (p1) at(-10,16) {\includegraphics[height=3.0cm,width=3cm]{main/2048pic/2_1.png}};
            
            
            \node (p2) at(-3,16) {\includegraphics[height=3.0cm,width=3cm]{main/2048pic/2_2.png}};
            
            \node (p3) at(3,16) {\includegraphics[height=3.0cm,width=3cm]{main/2048pic/3_1.png}};
            
            \node (p4) at(10,16) {\includegraphics[height=3.0cm,width=3cm]{main/2048pic/3_2.png}};
        
            \draw [-] (p1.north) -- (s11.south);
            \draw [-] (p2.north) -- (s12.south);
            \draw [-] (p3.north) -- (s21.south);
            \draw [-] (p4.north) -- (s22.south);
                
            
            \node (p5) at(-7,30) {\includegraphics[height=3.0cm,width=3cm]{main/2048pic/0.png}};
            
            \node (p6) at(10,25) {\includegraphics[height=3.0cm,width=3cm]{main/2048pic/2_0.png}};
    
            \node (p7) at(-10,25) {\includegraphics[height=3.0cm,width=3cm]{main/2048pic/2_0.png}};
            
            \draw [-] (st.west) -- (p5.east);
            \draw [-] (as1.west) -- (p7.east);
            \draw [-] (as2.east) -- (p6.west);
            
            
        \end{tikzpicture}
    \caption{ 2048的一个例子}
    \label{sttree}
    \end{figure*}