A:排除号码:
排除前区:04,06,07,09,12,22,30,31=0-1
排除后区:01,03,04,10
B:龙头凤尾:
龙头关注:01或03
凤尾关注:26或28
C:前区方案:
a-10码:01,03,08,11,16,18,23,24,26,28
b-14码:01,03,08,11,16,18,21,23,24,25,26,27,28,29
c-18码:01,02,03,08,11,14,15,16,18,20,21,23,24,25,26,27,28,29D:后区方案:
后区2码:07,09
后区4码:02,05,07,09
后区6码:02,05,06,07,08,09