documentclass[12pt,pstricks,border=15pt]{standalone}
usepackage{newcent}
begin{document}
begin{pspicture}(0,0)(3,3)
pscustom[fillstyle=solid,fillcolor=yellow,opacity=.5]{
psarcn(3,0){3}{180}{90}
psarcn(1,3){2}{0}{-90}
psarc(1,2){1}{-90}{0}
psarc(2,0){2}{90}{180}
  }
pscustom[fillstyle=solid,fillcolor=blue,opacity=.5]{
psarc(0,3){3}{-90}{0}
psarcn(1,3){2}{0}{-90}
psarcn(2,1){1}{180}{90}
psarc(2,0){2}{90}{180}
closepath
 }
end{pspicture}
end{document}