ABAP uses IN Range Table to make judgments

DATA:
  lt_range TYPE RANGE OF p_data,
  ls_range LIKE LINE OF lt_range.

 ls_range-sign = 'I'.
 ls_range-option = 'EQ'.
 ls_range-low = 'A100'.
 APPEND ls_range to lt_range.

 ls_range-low = 'A200'.
 APPEND ls_range to lt_range.

 ls_range-low = 'A300'.
 APPEND ls_range to lt_range.

IF p_code IN lt_range....
...