右边码的代码是数据集中的例子，为什么会提示错误啊
data contri;
input empid $ qtrnum $ amount;
cards;
e00224 qtr1 12
e00224 qtr2 33
e00224 qtr3 22
e00224 qtr4 .
e00224 qtr1 35
e00367 qtr1 35
e00367 qtr2 48
e00367 qtr4 30
e00441 qtr1 .
e00441 qtr2 63
e00441 qtr4 15
;
data a;
length goalamount 8;
if _N_=1 then do;
declare hash goal( );
goal.definekey("qtrnum");
goal.definedata("goalamount");
goal.definedone( );
call missing (qtrnum,goalamount);
goal.add(key:"qtr1",data:"10");
goal.add(key:"qtr2",data:"15");
goal.add(key:"qtr3",data:"5");
goal.add(key:"qtr4",data:"15");
end;
set contri;
goal.find( );
diff=amount-goalamount;
run;
proc print data=a;
run;