只用位操作在ABAP裡實現a+b
用ABAP實現下圖的第五種整數相加算法：
實現代碼：
REPORT zint.
PARAMETERS: a TYPE int4 OBLIGATORY DEFAULT 100,
b TYPE int4 OBLIGATORY DEFAULT 100.
DATA: threshold TYPE int4.
FORM add USING a TYPE int4 b TYPE int4 CHANGING cv_result TYPE int4.
DATA: n TYPE int4 VALUE 0,
c TYPE int4 VALUE 0.
DATA: i TYPE int4 VALUE 1.
DATA: boolean_a TYPE abap_bool,
boolean_b TYPE abap_bool,
_a TYPE int4,
_b TYPE int4,
aa TYPE int4,
bb TYPE int4.
DATA(wrapper_one) = zcl_integer=>value_of( 1 ).
DATA(wrapper_c) = zcl_integer=>value_of( c ).
aa = a.
bb = b.
WHILE i < threshold.
DATA(wrapper_a) = zcl_integer=>value_of( aa ).
DATA(wrapper_b) = zcl_integer=>value_of( bb ).
boolean_a = boolc( wrapper_a->and( wrapper_one )->get_raw_value( ) EQ 1 ).
boolean_b = boolc( wrapper_b->and( wrapper_one )->get_raw_value( ) EQ 1 ).
_a = COND int4( WHEN boolean_a EQ abap_true THEN 1 ELSE 0 ).
_b = COND int4( WHEN boolean_b EQ abap_true THEN 1 ELSE 0 ).
wrapper_a = zcl_integer=>value_of( _a ).
wrapper_b = zcl_integer=>value_of( _b ).
wrapper_c = zcl_integer=>value_of( c ).
DATA(_n_wrapper) = wrapper_a->xor( wrapper_b )->xor( wrapper_c ).
DATA(b_or_c) = wrapper_b->or( wrapper_c ).
DATA(b_and_c) = wrapper_b->and( wrapper_c ).
DATA(_c_wrapper) = wrapper_a->and( b_or_c )->or( b_and_c ).
c = _c_wrapper->get_raw_value( ).
DATA(_n_i0_wrapper) = zcl_integer=>value_of( COND int4( WHEN _n_wrapper->get_raw_value( ) > 0 THEN i ELSE 0 ) ).
DATA(wrapper_n) = zcl_integer=>value_of( n ).
n = wrapper_n->or( _n_i0_wrapper )->get_raw_value( ).
wrapper_a = zcl_integer=>value_of( aa ).
aa = wrapper_a->shift_right( )->get_raw_value( ).
wrapper_b = zcl_integer=>value_of( bb ).
bb = wrapper_b->shift_right( )->get_raw_value( ).
cv_result = n.
DATA(wrapper_i) = zcl_integer=>value_of( i ).
wrapper_i->shift_left( ).
i = wrapper_i->get_raw_value( ).
ENDWHILE.
ENDFORM.
START-OF-SELECTION.
DATA: i TYPE int4.
threshold = ipow( base = 2 exp = 30 ).
PERFORM add USING a b CHANGING i.
WRITE: / i.
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