内表中查找重复数据

REPORT zhello.

DATA: BEGIN OF item OCCURS 0,
        index TYPE i,
      END OF item.
DATA: in TYPE i.

item-index = 1.
APPEND item.
item-index = 2.
APPEND item.
item-index = 3.
APPEND item.
item-index = 2.
APPEND item.

SORT item by index.  "必须做排序动作
LOOP AT item.
  AT NEW index.
    in = 0.
  ENDAT.
  in = in + 1.
  AT END OF index.
    IF  in  NE 1.
      WRITE: 'double item'.
    ENDIF.
  ENDAT.
ENDLOOP.