plsql打印出99乘法表

declare
?????? x int;
?????? y int;
begin
???? x:=1;
????
???? while x<=9 loop
?????? y:=1;
?????? while y<=x loop
???????????? dbms_output.put(y || '*' || x || '=' || x*y || '? ');
???????????? y:=y+1;
?????? end loop;
?????? dbms_output.put_line('');
?????? x:=x+1;
???? end loop;
end;