how to remove non repetitive in sas as per below example

[ganeshmule]

data abcd;
input ID;
cards;
1
1
1
2
2
1
2
3
3
3
;
run;


answer would be like below :
Output:
1
1
1
2
2
3
3
3

[mkeintz · Accepted solution]

I think what you mean is to keep only the first group of records for any given ID:

data abcd;
input ID;
cards;
1
1
1
2
2
1
2
3
3
3
;
run;

data want;
  set abcd;
  by id notsorted;
  if _n_=1 then do;
    declare hash h();
      h.definekey('id');
      h.definedone();
  end;
  if h.check()=0 then delete;
  if last.id then h.add();
run;

[ganeshmule]

Thanks it works