阅读以下程序代码,回答后面的问题: MOV 18H , #00H ; ( 18H ) =00H MOV SP , #18H ; ( SP ) =18H MOV A , #30H ; ( A ) =30H MOV DPTR , #1023H ; ( DPTR ) =1023H PUSH A ; ( SP ) =19H ,( 19H ) =30H PUSH DPH ; ( SP ) =1AH ,( 1AH ) =10H PUSH DPL ; ( SP ) =1BH ,( 1BH ) =23H 执行以上程序后, ( 18H ) = ; (19H)= ; (1AH)= ( 1BH ) = ;( SP ) = ; 若要恢复以上的值,弹出堆栈,写出弹出堆栈的程序: ; (DPL)=00H (SP)=1AH ; (DPH)=10H (SP)=19H ; (A)=30H (SP)=18H 执行以上三条指令后,( SP ) = H 。