ANCOVA with Tukey tests | SAS Code Fragments

data test;
  input sub group dv cov ;
CARDS;
1      1      18      14
2      1      19      12
3      1      14      10
4      1      16      12
5      2      12      8
6      2      18      10
7      2      16      10
8      2      18      8
9      3      16      12
10      3      19      16
11      3      16      14
12      3      16      12
;
RUN;

PROC GLM DATA=test;
  CLASS group;
  MODEL dv = group cov ;
  LSMEANS group / ADJUST=TUKEY PDIFF ;
RUN;