上述程式的缺点为：在循环过程中，速度有所损失，而且用四位元查表也费事耗时。如果用一字元查表，则需增大「表」的对应值，再改为「总表」的方式，一次即可查到。且由第20行改起，并力求指令的精简，如：
20: MOV DX,OFFSET BYTETB
21: MVDB:
22: LODSB
23: SUB AH,AH
24: SHL AX,1 ; 一字元须变为二字元
25: ADD AX,DX ; 之位置以查表
26: MOV BX,AX ; BX可供间接定址用
27: MOV AX,[BX] ; 以一字元查表值
28: STOSW ; 查妥存入第一行
29: MOV [DI+4],AX ; 上下再重复一行
30: LODSB
31: SUB AH,AH ; 处
32: SHL AX,1 ; 理
33: ADD AX,DX
34: MOV BX,AX ; 第
35: MOV AX,[BX] ; 二
36: STOSW ; 列
37: MOV [DI+4],AX ;
38: LODSB ;
39: SUB AH,AH ; 处
40: SHL AX,1 ; 理
41: ADD AX,DX
42: MOV BX,AX ; 第
43: MOV AX,[BX] ; 三
44: STOSW ; 列
45: MOV [DI+4],AX ;
46: ADD DI,6 ; 再处理下一行
47: LOOP MVDB ; 共24次
48: DEC BP ; 做10,000次
49: JNZ S3 ; 完成
50: MOV AX,4C00H
51: INT 21H
52: RET
程式到此为止，下面还有一转换总表，可供各程式共用。
1:;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
2:; 转 换 表 ;
3:;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
4: BYTETB LABEL WORD
5: DB 000H,000H,000H,003H,000H,00CH,000H,00FH
6: DB 000H,030H,000H,033H,000H,03CH,000H,03FH
7: DB 000H,0C0H,000H,0C3H,000H,0CCH,000H,0CFH
8: DB 000H,0F0H,000H,0F3H,000H,0FCH,000H,0FFH
9: DB 003H,000H,003H,003H,003H,00CH,003H,00FH
10: DB 003H,030H,003H,033H,003H,03CH,003H,03FH
11: DB 003H,0C0H,003H,0C3H,003H,0CCH,003H,0CFH
12: DB 003H,0F0H,003H,0F3H,003H,0FCH,003H,0FFH
13: DB 00CH,000H,00CH,003H,00CH,00CH,00CH,00FH
14: DB 00CH,030H,00CH,033H,00CH,03CH,00CH,03FH
15: DB 00CH,0C0H,00CH,0C3H,00CH,0CCH,00CH,0CFH
16: DB 00CH,0F0H,00CH,0F3H,00CH,0FCH,00CH,0FFH
17: DB 00FH,000H,00FH,003H,00FH,00CH,00FH,00FH
18: DB 00FH,030H,00FH,033H,00FH,03CH,00FH,03FH
19: DB 00FH,0C0H,00FH,0C3H,00FH,0CCH,00FH,0CFH
20: DB 00FH,0F0H,00FH,0F3H,00FH,0FCH,00FH,0FFH
21: DB 030H,000H,030H,003H,030H,00CH,030H,00FH
22: DB 030H,030H,030H,033H,030H,03CH,030H,03FH
23: DB 030H,0C0H,030H,0C3H,030H,0CCH,030H,0CFH
24: DB 030H,0F0H,030H,0F3H,030H,0FCH,030H,0FFH
25: DB 033H,000H,033H,003H,033H,00CH,033H,00FH
26: DB 033H,030H,033H,033H,033H,03CH,033H,03FH
27: DB 033H,0C0H,033H,0C3H,033H,0CCH,033H,0CFH
28: DB 033H,0F0H,033H,0F3H,033H,0FCH,033H,0FFH
29: DB 03CH,000H,03CH,003H,03CH,00CH,03CH,00FH
30: DB 03CH,030H,03CH,033H,03CH,03CH,03CH,03FH
31: DB 03CH,0C0H,03CH,0C3H,03CH,0CCH,03CH,0CFH
32: DB 03CH,0F0H,03CH,0F3H,03CH,0FCH,03CH,0FFH
33: DB 03FH,000H,03FH,003H,03FH,00CH,03FH,00FH
34: DB 03FH,030H,03FH,033H,03FH,03CH,03FH,03FH
35: DB 03FH,0C0H,03FH,0C3H,03FH,0CCH,03FH,0CFH
36: DB 03FH,0F0H,03FH,0F3H,03FH,0FCH,03FH,0FFH
37: DB 0C0H,000H,0C0H,003H,0C0H,00CH,0C0H,00FH
38: DB 0C0H,030H,0C0H,033H,0C0H,03CH,0C0H,03FH
39: DB 0C0H,0C0H,0C3H,0C0H,0CCH,0C0H,0CFH,0C0H
40: DB 0C0H,0F0H,0C0H,0F3H,0C0H,0FCH,0C0H,0FFH
41: DB 0C3H,000H,0CH3,003H,0C3H,00CH,0C3H,00FH
42: DB 0C3H,030H,0C3H,033H,0C3H,03CH,0C3H,03FH
43: DB 0C3H,0C0H,0C3H,0C3H,0C3H,0CCH,0C3H,0CFH
44: DB 0C3H,0F0H,0C3H,0F3H,0C3H,0FCH,0C3H,0FFH
45: DB 0CCH,000H,0CCH,003H,0CCH,00CH,0CCH,00FH
46: DB 0CCH,030H,0CCH,033H,0CCH,03CH,0CCH,03FH
47: DB 0CCH,0C0H,0CCH,0C3H,0CCH,0CCH,0CCH,0CFH
48: DB 0CCH,0F0H,0CCH,0F3H,0CCH,0FCH,0CCH,0FFH
49: DB 0CFH,000H,0CFH,003H,0CFH,00CH,0CFH,00FH
50: DB 0CFH,030H,0CFH,033H,0CFH,03CH,0CFH,03FH
51: DB 0CFH,0C0H,0CFH,0C3H,0CFH,0CCH,0CFH,0CFH
52: DB 0CFH,0F0H,0CFH,0F3H,0CFH,0FCH,0CFH,0FFH
53: DB 0F0H,000H,0F0H,003H,0F0H,00CH,0F0H,00FH
54: DB 0F0H,030H,0F0H,033H,0F0H,03CH,0F0H,03FH
55: DB 0F0H,0C0H,0F0H,0C3H,0F0H,0CCH,0F0H,0CFH
56: DB 0F0H,0F0H,0F0H,0F3H,0F0H,0FCH,0F0H,0FFH
57: DB 0F3H,000H,0F3H,003H,0F3H,00CH,0F3H,00FH
58: DB 0F3H,030H,0F3H,033H,0F3H,03CH,0F3H,03FH
59: DB 0F3H,0C0H,0F3H,0C3H,0F3H,0CCH,0F3H,0CFH
60: DB 0F3H,0F0H,0F3H,0F3H,0F3H,0FCH,0F3H,0FFH
61: DB 0FCH,000H,0FCH,003H,0FCH,00CH,0FCH,00FH
62: DB 0FCH,030H,0FCH,033H,0FCH,03CH,0FCH,03FH
63: DB 0FCH,0C0H,0FCH,0C3H,0FCH,0CCH,0FCH,0CFH
64: DB 0FCH,0F0H,0FCH,0F3H,0FCH,0FCH,0FCH,0FFH
65: DB 0FFH,000H,0FFH,003H,0FFH,00CH,0FFH,00FH
66: DB 0FFH,030H,0FFH,033H,0FFH,03CH,0FFH,03FH
67: DB 0FFH,0C0H,0FFH,0C3H,0FFH,0CCH,0FFH,0CFH
68: DB 0FFH,0F0H,0FFH,0F3H,0FFH,0FCH,0FFH,0FFH
69: CG ENDS
70: END START
本程式因为加了个转换表，空间增大为1471字元，但速度却加快为2.5 秒，这是空间换时间的最佳例证。
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