data OaklandAreaCodes;
  set sashelp.zipcode(keep=StateName City AreaCodes);
  where City="Oakland" and StateName ne "California";
  array AClist {3} $ 3 AreaCode1-AreaCode3;
  do i=1 to 3;
    AreaCode=scan(AreaCodes,i);
    if AreaCode=" " then i=3;
    else if i=1 then ACList{1}=AreaCode;
    else if AreaCode > ACList{i-1} then ACList{i}=AreaCode;
    else do;
      if i=3 then ACList{3}=ACList{2};
      if i>=2 then ACList{2}=ACList{1};
      ACList{1}=AreaCode;
    end;
  end;
  keep StateName AreaCodes AreaCode1-AreaCode3;
run;
proc print data=OaklandAreaCodes;
  title1 "Area Codes for Cities named Oakland";
  title2 "(outside of California)";
run;