u=1.7cm;
r=3pt;

beginfig(1);
for i=0 upto 5:  z[i]=u*dir(180-60*i);  endfor
draw z1--z2--z3--z4--z5--z0--z1--z4;
pickup pencircle scaled 2r;
for i=0 upto 5:  draw z[i];  endfor
label.lft(btex\it1etex, z0+r*dir180);
label.ulft(btex\it2etex, z1+r*dir135);
label.urt(btex\it3etex, z2+r*dir45);
label.rt(btex\it4etex, z3+r*dir0);
label.lrt(btex\it5etex, z4+r*dir-45);
label.llft(btex\it6etex, z5+r*dir-135);
label.ulft(btex$e_1$etex, 0.5[z0,z1]);
label.lrt("4", 0.5[z0,z1]);
label.llft(btex$e_2$etex, 0.5[z0,z5]);
label.urt("2", 0.5[z0,z5]);
label.top(btex$e_3$etex, 0.5[z1,z2]);
label.bot("3", 0.5[z1,z2]);
label.urt(btex$e_4$etex, 0.5[z1,z4]);
label.llft("3", 0.5[z1,z4]);
label.urt(btex$e_5$etex, 0.5[z2,z3]);
label.llft("2", 0.5[z2,z3]);
label.lrt(btex$e_6$etex, 0.5[z3,z4]);
label.ulft("1", 0.5[z3,z4]);
label.bot(btex$e_7$etex, 0.5[z4,z5]);
label.top("3", 0.5[z4,z5]);
endfig;

end;