
\begin{tikzpicture}

\tikzstyle{node1}=[inner sep=0mm,minimum height=1em,minimum width=3em,fill=ugreen!10!blue!10]
\tikzstyle{node2}=[inner sep=0mm,minimum height=1em,minimum width=3em,fill=ugreen!20!blue!20]
\tikzstyle{node3}=[inner sep=0mm,minimum height=1em,minimum width=3em,fill=ugreen!30!blue!30]
\tikzstyle{node4}=[inner sep=0mm,minimum height=1em,minimum width=3em,fill=ugreen!40!blue!40]
\tikzstyle{node5}=[inner sep=0mm,minimum height=1em,minimum width=3em,fill=ugreen!50!blue!50]

\begin{scope}

\node[anchor=north west] (l1) at (0,0) {易};
\node[anchor=west] (l2) at ([xshift=10.3em,yshift=0em]l1.east) {难};

\draw [->,thick] ([xshift=-2em,yshift=-1em]l1.south) --  ([xshift=2em,yshift=-1em]l2.south);

\node[anchor=north,node1] (c1) at ([xshift=0em,yshift=-2em]l1.south) {};
\node[anchor=west,node2] (c2) at ([xshift=0em,yshift=0em]c1.east) {};
\node[anchor=west,node3] (c3) at ([xshift=0em,yshift=0em]c2.east) {};
\node[anchor=west,node4] (c4) at ([xshift=0em,yshift=0em]c3.east) {};
\node[anchor=west,node5] (c5) at ([xshift=0em,yshift=0em]c4.east) {};

\node[anchor=north] (lb1) at ([xshift=0em,yshift=-1.5em]c3.south) {(a)样本难易程度图示};

\end{scope}

\begin{scope}[yshift = -1.7in]
\foreach \i / \j / \z in 
		{0/0/node1, 1/0/node1, 2/0/node1, 3/0/node1, 4/0/node1, 5/0/node1, 6/0/node1,
		 1/1/node2, 2/1/node2, 3/1/node2, 4/1/node2, 5/1/node2, 6/1/node2,
		 2/2/node3, 3/2/node3, 4/2/node3, 5/2/node3, 6/2/node3,
		 3/3/node4, 4/3/node4, 5/3/node4, 6/3/node4,
		 4/4/node5, 5/4/node5, 6/4/node5,
		}
	\node[anchor=north west,\z,draw=white](n\i\j) at (1.0*3em*\j + 0*0em,-1.0*1em*\i + 0*0em){};

	\node[anchor=north west,node1,draw=white](nc) at (0,0){};

\draw [->,very thick] ([xshift=-1em,yshift=1em]n00.north west) --  ([xshift=16em,yshift=1em]n00.north west);
\draw [->,very thick] ([xshift=-1em,yshift=1em]n00.north west) --  ([xshift=-1em,yshift=-9em]n00.north west);

\node[anchor=west] (x1) at ([xshift=12em,yshift=2em]n00.north west) {数据块};
\node[anchor=east] (y1) at ([xshift=-1em,yshift=-7.5em]n00.north west) {轮次};
\node[anchor=west,font=\small] (t1) at ([xshift=0em,yshift=-1em]n60.south west) {$\ldots$直到模型收敛};

\node[anchor=north] (lb2) at ([xshift=0em,yshift=-3em]n62.south) {(b)不同训练阶段使用的数据};

\end{scope}

\end{tikzpicture}