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V0代表當前隊列中數量   V0=0  D0V0=A
                                            V0=2  D0V0=C
                                         ……
                                            V0=4  D0V0=E
V1代表執行順序   D0V1   V1=0
                                ……
                                D0V1    V1=4
                             判斷  V1是否大于V0
                            大于   則表示執行完畢，V1=V0 =0