1 \usepackage{tikz}

     2 %\usepackage{pgf}

     3 %\usetikzlibrary{positioning}

     4 %\usetikzlibrary{calc}

     5 %\usetikzlibrary{automata}

     6 %\usetikzlibrary{arrows}

     7 %\usetikzlibrary{backgrounds}

     8 %\usetikzlibrary{fit}

     9 %\usepackage{tikz-qtree}

    10 \usepackage{pgfplots}

    11 

    12 %\pgfplotsset{compat=1.15}