Cfrtjryk

documentclass[12pt,a4paper]{article}

usepackage{amsmath,amssymb}

usepackage[utf8]{vietnam}

usepackage{pstricks,pst-node} % required package

usepackage{auto-pst-pdf} 

begin{document}

begin{pspicture}    

psmatrix[linecolor=red,mnode=Circle,radius=3mm,colsep=1.25cm,rowsep=1.25cm]

   [name=2] 2 &  & [name=3] 3 \

              &[name=5] 5 \

   [name=1] 1 &  & [name=4] 4

psset{linecolor=blue,arrowscale=1.5}



ncline{->}{3}{2}

ncline{->}{4}{3}

ncline{->}{4}{5} 

ncline{->}{5}{3}

ncline{->}{5}{1}

ncline{->}{1}{4}



nccurve[angleA=80,angleB=25,ncurv=5]{->}{3}{3}



ncarc[arcangle=22]{->}{1}{2}

ncarc[arcangle=22]{->}{2}{1}

endpsmatrix 



end{pspicture}

end{document}

How to draw Picture 1 like as Picture 2?(I see, 2 is more beautiful than 1)

How to compact ncline or we can only typing manually? It means is there a macro like as ncline{->}{3}{2}{->}{4}{3}{->}{4}{5}... ?

Picture 1:

Picture 2:

The code of Picture 2 ( use tikz )

documentclass[tikz,border=3mm]{standalone}

begin{document}

begin{tikzpicture}

[every node/.style={circle,draw=red},

 every path/.style={blue,-latex,thick}]

defa{2}

node (5) at (0,0) {$5$};

node (1) at (-a,-a) {$1$};

node (2) at (-a,a) {$2$};

node (3) at (a,a) {$3$};

node (4) at (a,-a) {$4$};

draw (1)--(4); draw (4)--(3);

draw (3)--(2); draw (5)--(3);

draw (5)--(1); draw (4)--(5);

draw (2) to[out=-70,in=70] (1);

draw (1) to[out=110,in=-110] (2);

draw (3) .. controls +(80:1) and +(30:1) .. (3); % <<<---- notice!

end{tikzpicture}

end{document}

define your own macro and for the loop use symmetrical angles with respect to 45 degrees::

documentclass{article}

usepackage{pst-node} % required package

usepackage{auto-pst-pdf} 



makeatletter

newcommandNCline[3]{ncline{#1}{#2}{#3}@ifnextcharbgroupNCline{}}

makeatother

begin{document}

 psmatrix[linecolor=red,mnode=Circle,radius=3mm,colsep=1.25cm,rowsep=1.25cm]

    [name=2] 2 &            & [name=3] 3 \

               &[name=5] 5 \

    [name=1] 1 &            & [name=4] 4

psset{linecolor=blue,arrowscale=1.5}

NCline{->}{3}{2}{->}{4}{3}{->}{4}{5}{->}{5}{3}{->}{5}{1}{->}{1}{4}

nccurve[angleA=75,angleB=15,ncurv=6]{->}{3}{3}



ncarc[arcangle=22]{->}{1}{2}

ncarc[arcangle=22]{->}{2}{1}

endpsmatrix 



end{document}