请教一个问题,如何用latex将下图变成一个正十二边形?
$$xymatrix@R=0.5cm@C=0.7cm{
&&&overset{a_{1,1}}{bullet}&&&\
&&overset{a_{1,12}}{bullet}&&overset{a_{1,2}}{bullet}&&\
&overset{a_{1,11}}{bullet}&&&&overset{a_{1,3}}{bullet}&\
underset{a_{1,10}}{bullet}&&&&&&underset{a_{1,4}}{bullet}\
&underset{a_{1,9}}{bullet}&&&&underset{a_{1,5}}{bullet}&\
&&underset{a_{1,8}}{bullet}&&underset{a_{1,6}}{bullet}&&\
& & & overset{a_{1,7}}{bullet} & & &
ar"1,4";"2,3"_{alpha_{0,0}}
ar"2,3";"3,2"_{alpha_{0,1}}
ar"3,2";"4,1"_{alpha_{0, 2}}
ar"4,1";"5,2"_{alpha_{0,11}}
ar"5,2";"6,3"_{alpha_{0,10}}
ar"6,3";"7,4"_{alpha_{0,3}}
ar"7,4";"6,5"_{alpha_{0,9}}
ar"6,5";"5,6"_{alpha_{0,4}}
ar"5,6";"4,7"_{alpha_{0,8}}
ar"4,7";"3,6"_{alpha_{0,5}}
ar"3,6";"2,5"_{alpha_{0,7}}
ar"2,5";"1,4"_{alpha_{0, 6}}
}$$