排除前区:04,12,19,23,26,33,34,35=0-1
排除后区:01,04,07,12
B:龙头凤尾:
龙头关注:07或08
凤尾关注:29或31
C:前区方案:
a-10码:07,08,09,11,15,20,21,24,29,31
b-14码:02,06,07,08,09,10,11,15,20,21,24,25,29,31
c-18码:01,02,06,07,08,09,10,11,13,15,20,21,24,25,28,29,31,32
D:后区方案:
后区2码:03,05
后区4码:03,05,09,10
后区6码:02,03,05,06,09,10