\begin{tikzpicture}

    \def \h{4}

    %Pipeline
    \node[rectangle,draw=red] (s) at (2*\h,0) {Sensitive attribute};
    \node[rectangle,draw=blue] (inf) at (0,0) {Classification};
    \node[rectangle,draw=blue] (att) at (\h,0) {Attack};
    \draw[->,color=blue] (inf) to (att);
    \draw[->,color=red] (att) to (s);

    %Ensembles
    \node (c0) at (0,1) {$E=\{0,\cdots,m-1\}$};
    
    \node (a0) at (2*\h,1) {$F=\{0,\cdots,n-1\}$};

    \draw[->] (c0) to (a0);



\end{tikzpicture}

