with t as(
select 'A' tid,1 flg from dual
union all
select 'A',2 from dual
union all
select 'A',3 from dual
union all
select 'B',1 from dual
union all
select 'C',1 from dual
union all
select 'C',2 from dual
union all
select 'C',2 from dual
)
select tid, flg, count(1) c
  from t t1
 where not exists (select 1
          from t t2
         where t1.tid = t2.tid
           and t2.flg > t1.flg)
 group by tid, flg order by tid

TID        FLG          C
--- ---------- ----------
A            3          1
B            1          1
C            2          2