关于pl/sql编程的问题

看看这个程序哪错了，本人刚学，啥也不会。
CREATE OR REPLACE PROCEDURE lvkaihua1
(
C_NAME VARCHAR2,
C_PASSWORD VARCHAR2,
FLAG OUT NUMBER)
IS
COUNTS NUMBER;
PCOUNTS NUMBER;
BEGIN
SELECT COUNT(*) INTO COUNTS FROM USERS WHERE USERS=C_NAME;
IF COUNTS>0 THEN
SELECT COUNT(*) INTO PCOUNTS FROM USERS WHERE PASSWD=C_PASSWORD;
IF PCOUNTS>0 THEN
FLAG:=1;
else
flag：=-1；
END IF;
ELSE
FLAG:=-1;
END IF;
END lvkaihua1;