第五章基本结构程序参考答案

1,第五章课后习题参考答案,P86_4.16 若在数组字变量AQTAB平方表中有十进制数020的平方值，从表中找出16的平方值，结果送字变量NUM单元中。,参考答案,DATA SEGMENT AQTAB DW 0,1,4,9,16,25,36,49,64,81,100,121,144 DW 169,196,225,256,289,324,361,400 BUF DW 16 NUM DW ?DATA ENDSCODE SEGMENT ASSUME CS:CODE,DS:DATABEGIN:MOV AX,DATA MOV DS, AX MOV BX , OFFSET AQTAB MOV AX, BUF ADD AX,AX ADD BX, AX,MOV AX, BX MOV NUM , AX MOV AH,4CH INT 21H CODE ENDS END BEGIN,P86_4.17 计算D=B*2-4AC，设A=2,B=9,C=8,结果存放在RESUT中。,DATA SEGMENT A DB 2 B DB 9 C DB 8 RESULT DW ? ,?DATA ENDSCODE SEGMENT ASSUME DS:DATA,CS:CODESTART:MOV AX,DATA MOV DS,AX,MOV AL,2 IMUL B CWD MOV BX,DX MOV CX,AX MOV AL,A IMUL C MOV DX,4 IMUL DX SUB CX,AX SBB BX,DX MOV RESULT,CX MOV RESULT+2,BX MOV AH,4CH INT 21H CODE ENDS ENDSTART,P102_5.6参考答案1,BUF1偶数?,Y,N,开始,结束,BUF2偶数?,Y,N,BUF1与BUF2交换,BUF2偶数?,Y,N,BUF1中数1BUF2中数1,DATA SEGMENT BUF1 DB 30H BUF2 DB 23HDATA ENDSCODE SEGMENT ASSUME DS:DATA,CS:CODESTART:MOV AX,DATA MOV DS,AX MOV AL,BUF1 MOV BL,BUF2 TEST AL,01H JZ OS1 ;BUF1中为偶数 TEST BL,01H JZ EXIT ;BUF1中奇数,BUF2为偶数 INC BUF1 ;均为奇数 INC BUF2 JMP EXIT,OS1: TEST BL,01H JZ EXIT ;均为偶数 MOV BUF1,BL ;BUF1中偶数,BUF2为奇数 MOV BUF2,ALEXIT: MOV AH,4CH INT 21H CODE ENDS ENDSTART,BUF2偶数?,Y,N,开始,结束,N,BUF1与BUF2交换,BUF1偶数?,Y,BUF11;BUF21,P102_5.6参考答案2,DATA SEGMENT BUF1 DB 30H BUF2 DB 23HDATA ENDSCODE SEGMENT ASSUME DS:DATA ASSUME CS:CODESTART:MOV AX,DATA MOV DS,AX MOV AL,BUF1 MOV BL,BUF2 TEST BL,01H JZ EXIT ;BUF2中为偶数 TEST AL,01H JZ JIAOHUAN ;BUF1中偶数,BUF2为奇数,INC BUF1 ;均为奇数 INC BUF2 JMP EXIT JIAOHUAN:MOV BUF1,BL MOV BUF2,ALEXIT: MOV AH,4CH INT 21H CODE ENDS ENDSTART,DATA SEGMENT BUF DB 30H,02H,10H,11H,56H,78H,65H,54H,85H,19H CNT EQU $-BUF SUM DB ?DATA ENDSCODE SEGMENT ASSUME CS:CODE, DS:DATASTART:MOV AX,DATA MOV DS,AX MOV SI,OFFSET BUF MOV CX, CNT MOV AX, 0,P102_57,ADD1: ADD AL,SI ADC AH,0 INC SI LOOP ADD1 MOV CL,CNT DIV CL MOV SUM, AL MOV AH, 4CH INT 21HCODE ENDS END START,DATA SEGMENT X DW -123 Y DW 50 Z DW 1234HDATA ENDSCODE SEGMENT ASSUME DS:DATA,CS:CODESTART:MOV AX,DATA MOV DS,AX MOV AX,X MOV BX,Y MOV CX,Z CMP AX,BX JGE L1,P102_58,CMP BX,CX JL L2 MOV AX,BX JMP EXITL2: MOV AX,CX JMP EXITL1: CMP AX,CX JL L2EXIT:MOV AH,4CH INT 21H CODE ENDS ENDSTART,P102_5.9从STRING开始存放一以为结束标志的字符串，把字符串中的字符分类，数字送入NUM开始的内存区，大写字母送入BCHAR开始的内存区，小写字母送入LCHAR开始的内存区，其它字符存到OTHER开始的内存区。,参考程序1：DATA SEGMENT STRING DB 1$2AaDd# CNT EQU $-STRING-1 NUM DB CNT DUP (?) BCHAR DB CNT DUP(?) LCHAR DB CNT DUP(?) OTHER DB CNT DUP(?)DATA ENDSCODE SEGMENT ASSUME CS:CODE, DS:DATASTART: MOV AX,DATA MOV DS,AX,MOV SI,OFFSET STRING MOV DI,OFFSET NUM MOV BP,OFFSET BCHAR MOV CX,OFFSET LCHAR MOV DX,OFFSET OTHER LOP1: MOV AL,SI CMP AL,# JZ EXIT CMP AL,0 JB OTHER1 CMP AL,9 JBE NUM1 CMP AL,A JB OTHER1 CMP AL,Z JBE BCHAR1 CMP AL,a JB OTHER1 CMP AL,z JA OTHER1,LCHAR1: MOV BX,CX MOV BX,AL INC CX JMP NEXTBCHAR1: MOV DS:BP,AL INC BP JMP NEXTNUM1: MOV DI,AL INC DI JMP NEXTOTHER1: MOV BX,DX MOV BX,AL INC DXNEXT: INC SI JMP LOP1EXIT: MOV AH,4CH INT 21HCODE ENDS END START,参考程序2：DATA SEGMENT STRING DB 1$2AaDd# CNT EQU $-STRING-1 NUM DB CNT DUP (?) BCHAR DB CNT DUP(?) LCHAR DB CNT DUP(?) OTHER DB CNT DUP(?) ADD1 DW ?,?,?,?DATA ENDSCODE SEGMENT ASSUME CS:CODE ASSUME DS:DATA,START: MOV AX,DATA MOV DS,AX MOV SI,OFFSET STRING MOV DI,OFFSET NUM MOV ADD1,DI MOV DI,OFFSET BCHAR MOV ADD1+2,DI MOV DI,OFFSET LCHAR MOV ADD1+4,DI MOV DI,OFFSET OTHER MOV ADD1+6,DI,LOP1: MOV AL,SI CMP AL,# JZ EXIT CMP AL,0 JB OTHER1 CMP AL,9 JBE NUM1 CMP AL,A JB OTHER1 CMP AL,Z JBE BCHAR1 CMP AL,a JB OTHER1 CMP AL,z JA OTHER1 LCHAR1: MOV BX,ADD1+2 MOV BX,AL INC ADD1+2 JMP NEXT,BCHAR1: MOV BX,ADD1+4 MOV BX,AL INC ADD1+4 JMP NEXTNUM1: MOV BX,ADD1 MOV BX,AL INC ADD1 JMP NEXTOTHER1: MOV BX,ADD1+6 MOV BX,AL INC ADD1+6NEXT: INC SI JMP LOP1EXIT: MOV AH,4CH INT 21HCODE ENDS END START,ERR：DATA SEGMENT STRING DB 1$2AaDd# CNT EQU $-STRING-1 NUM DB CNT DUP (?) BCHAR DB CNT DUP(?) LCHAR DB CNT DUP(?) OTHER DB CNT DUP(?)DATA ENDSCODE SEGMENT ASSUME CS:CODE,DS:DATASTART: MOV AX,DATA MOV DS,AX MOV SI,OFFSET STRING,LOP1: MOV AL,SI CMP AL,# JZ EXIT CMP AL,0 JB OTHER1 CMP AL,9 JBE NUM1 CMP AL,A JB OTHER1 CMP AL,Z JBE BCHAR1 CMP AL,a JB OTHER1 CMP AL,z JA OTHER1 LCHAR1:MOV LCHAR,AL INC LCHAR JMP NEXT,BCHAR1:MOV BCHAR,AL INC BCHAR JMP NEXTNUM1: MOV NUM,AL INC NUM JMP NEXTOTHER1:MOV OTHER,AL INC OTHERNEXT: INC SI JMP LOP1EXIT: MOV AH,4CH INT 21HCODE ENDS END START,P102_5.10,DATA SEGMENT SCORE DB 96,87,88,85,78,67,77,90,81,100 DB 92,81,83,89,71,61,74,95,88,100 CNT EQU $-SCORE G6 DB ? G7 DB ? G8 DB ? G9 DB ? G10 DB ?DATA ENDSCODE SEGMENT ASSUME CS:CODE, DS:DATASTART: MOV AX,DATA MOV DS,AX MOV SI,OFFSET SCORE MOV CX,CNT,LOP1: MOV AL,SI CMP AL,69 JBE N6 CMP AL,79 JBE N7 CMP AL,89 JBE N8 CMP AL,99 JBE N9 INC G10 JMP NEXT,N6: INC G6 JMP NEXTN7: INC G7 JMP NEXTN8: INC G8 JMP NEXTN9: INC G9NEXT: INC SI LOOP LOP1EXIT: MOV AH,4CH INT 21HCODE ENDS END START,20,P126_6.5 参考程序,CODE SEGMENT ASSUME CS:CODE START:MOV AX,0 MOV BX,1LOP1: ADD AX,BX CMP AX,8000 JAE NEXT INC BX JMP LOP1NEXT: DEC BX ;BX为最大X值 MOV AH,4CH INT 21HCODE ENDS END START,21,P126_6.6 计算N！（0N6，6!=720）。,DATA SEGMENT RES DW ?DATA ENDSCODE SEGMENT ASSUME CS:CODE START:MOV AX,DATA MOV DS,AX MOV AH,1 INT 21H SUB AL,30H MOV CL,AL MOV AL,1 MOV BL,0,LOP1:INC BL CMP CL,BL JB NEXT MUL BL JMP LOP1NEXT:MOV RES,AX MOV AH,4CH INT 21HCODE ENDS END START,22,P126_6.6 计算N！（0N9，8!=40320）。,DATA SEGMENT RES DW ?,?DATA ENDSCODE SEGMENT ASSUME CS:CODE,DS:DATA START:MOV AX,DATA MOV DS,AX MOV AH,1 INT 21H SUB AL,30H MOV AH,0 MOV DX,0 MOV CX,AX,CMP AX,1 JZ NEXT MOV AX,1 MOV BX,1LOP1:INC BX MUL BX CMP BX,CX JB LOP1 NEXT:MOV RES,AX MOV RES+2,DX MOV AH,4CH INT 21HCODE ENDS END START,23,P126_6.7 参考程序1,DATA SEGMENT STR DB ASAAAASAAASAAAAAAAAAA CNT EQU $-STR RESU DB ?DATA ENDSCODE SEGMENT ASSUME CS:CODE, DS:DATASTART:MOV AX,DATA MOV DS,AX MOV CX,CNT MOV BX,0 MOV AX,0COUNT:CMP STRBX,A,JZ A_NO JMP NEXTA_NO: INC ALNEXT: INC BX DEC CX JNZ COUNT MOV RESU,AL,MOV CL,4 SHR AL,CL CMP AL,9 JBE NEXT1 ADD AL,7NEXT1:ADD AL,30H MOV DL,AL MOV AH,2 INT 21H MOV AL,RESU AND AL,0FH CMP AL,9 JBE NEXT2 ADD AL,7,NEXT2:ADD AL,30H MOV DL,AL MOV AH,2 INT 21H MOV DL,H MOV AH,2 INT 21H MOV AH,4CH INT 21HCODE ENDS END START,25,P126_6.7 参考程序2,DATA SEGMENT STR DB ASAAAASAAASAAAAAAAAAA CNT EQU $-STR RESU DB ?DATA ENDSCODE SEGMENT ASSUME CS:CODE, DS:DATASTART:MOV AX,DATA MOV DS,AX MOV CX,CNT MOV BX,OFFSET STR MOV AX,0COUNT:CMP BX,A,JZ A_NO JMP NEXTA_NO: INC ALNEXT: INC BX DEC CX JNZ COUNT MOV RESU,AL,MOV CL,4 SHR AL,CL MOV CX,1NEXT1:CMP AL,9 JBE NEXT2 ADD AL,7NEXT2:ADD AL,30H MOV DL,AL MOV AH,2 INT 21H JCXZ NEXT3 MOV CX,0 MOV AL,RESU AND AL,0FH JMP NEXT1,NEXT3:MOV DL,H MOV AH,2 INT 21H MOV AH,4CH INT 21HCODE ENDS END START,27,P126_6.8 参考程序,DATA SEGMENT BUFA DB 12H,02H,48H,13H CNT1 EQU $-BUFA BUFB DB 01H,12H,48H,18H,13H CNT2 EQU $-BUFB BUFC DB CNT1 DUP (?)DATA ENDSCODE SEGMENT ASSUME CS:CODE,DS:DATA,ES:DATASTART:MOV AX,DATA MOV DS,AX MOV ES,AX MOV SI,OFFSET BUFA MOV BX,OFFSET BUFC MOV DX,CNT1,LOP1:MOV DI,OFFSET BUFB MOV CX,CNT2 MOV AL,SI CLD REPNZ SCASB JZ FOUND JMP NEXTFOUND:MOV BX,AL INC BXNEXT:INC SI DEC DX JNZ LOP1 MOV AH,4CH INT 21HCODE ENDS END START,28,P126_6.9 参考程序1,DATA SEGMENT DATA1 DB 3,-40,6,7,9,2,0,-10,20 CNT EQU $-DATA1 MAX DB ? MAXP DB ? MIN DB ? MINP DB ?DATA ENDSCODE SEGMENT ASSUME CS:CODE,DS:DATASTART:MOV AX,DATA MOV DS,AX,MOV CX,CNT-1 MOV BX,OFFSET DATA1 MOV AL,BX MOV MAX,AL MOV MAXP,BL MOV MIN,AL MOV MINP,BLLOP1: INC BX MOV AL,BX CMP AL,MAX JLE LOP2,MOV MAX,AL MOV MAXP,BL JMP LOP3LOP2: CMP AL,MIN JGE LOP3 MOV MIN,AL MOV MINP,BLLOP3: LOOP LOP1 MOV AH,4CH INT 21H CODE ENDS END START,30,P126_6.9 参考程序2,DATA SEGMENT DATA1 DB 3,-40,6,7,9,2,0,-10,20 CNT EQU $-DATA1 MAX DB ? MAXP DB ? MIN DB ? MINP DB ?DATA ENDSCODE SEGMENT ASSUME CS:CODE,DS:DATASTART:MOV AX,DATA MOV DS,AX,MOV CX,CNT-1 MOV BX,0 MOV AX,0 MOV DX,0 MOV AL,DATA1BX MOV DL,BLLOP1:INC BX CMP AL,DATA1BX JGE LOP2 MOV AL,DATA1BX MOV DL,BLLOP2:LOOP LOP1 MOV MAX,AL MOV MAXP,DL;求最大值及下标,MOV CX,CNT-1 MOV AX,0 MOV BX,0 MOV DX,0 MOV AL,DATA1BX MOV DL,BLLOP3: INC BX CMP AL,DATA1BX JLE LOP4 MOV AL,DATA1BX MOV DL,BLLOP4: LOOP LOP3 MOV MIN,AL MOV MINP,DL;求最小值及下标 MOV AH,4CH INT 21H CODE ENDS END START,32,第五章习题参考答案,5.1 已知某班学生的英语成绩按学号（从1开始）从小到大的顺序排列在TAB表中，要查的学生的学号放在NO所指向的存储单元中。 编写程序查找学号为10的学生的成绩。查表结果放在ENGLISH所指向的存储单元中。5.2 已知在X单元中存放着一个8位无符号数，判断该数的奇偶性。如是奇数存入N1单元，否则存入N2单元。5.3 从STR开始存放一字符串，统计串中字符A的个数，存放在RESU字节单元。5.4 从BUF开始存放若干带符号字节数据，将它们相加并将结果（超过一字节范围）存放到字单元SUM中。,5.5 将两个多字节压缩BCD码相加，假定两个压缩BCD码分别从BCD1、BCD2开始存放，结果从BCD3开始存放。5.6 设从STRING开始存放一以为结束标志的字符串，把字符串中的字符分类，数字送入NUM开始的内存区，字母送入CHAR开始的内存区，其它字符存到OTHER开始的内存区。5.7 找出首地址为BUF的包含若干个带符号字节数据的数据块中的最小偶数，结果放在RESU字节单元中，并以16进制形式显示在屏幕上。5.8 在地址为TABLE的字数据块中存放按升序排列的若干带符号数，把出现次数最多的数及出现的次数分别存入RESU1、RESU2字单元。 5.9 在屏幕上打印1050之间能被7整除的数。,34,参考答案,5.1 某班学生英语成绩按学号（从1开始）从小到大的顺序排列在TAB表中，要查的学生的学号放在NO所指向的存储单元中。编程查找学号为8的学生的成绩。查表结果放在ENGLISH所指向的存储单元中。,DATA SEGMENT ORG 1 TAB DB 80, 85, 86, 71, 98 , 83, 56, 32, 66, 100 NO DB 8 ENGLISH DB ？DATA ENDSCODE SEGMENT ASSUME DS：DATA , CS：CODEBEGIN：MOV AX , DATA MOV DS , AX MOV BX , 0 MOV AH , 0 MOV AL , NO ADD BX , AX MOV AL , BX MOV ENGLISH , AL MOV AH , 4CH INT 21HCODE ENDS END BEGIN,DATA SEGMENT NO DB 8 TAB DB 80, 85, 86, 71, 98 , 83, 56, 32, 66, 100 ENGLISH DB ？DATA ENDSCODE SEGMENT ASSUME DS：DATA , CS：CODEBEGIN：MOV AX , DATA MOV DS , AX LEA BX , NO MOV AL , NO XLAT MOV ENGLISH , AL MOV AH , 4CH INT 21HCODE ENDS END BEGIN,5.2已知在X单元中存放着一个8位无符号数，判断该数的奇偶性。如是奇数存入N1单元，否则存入N2单元。,DATA SEGMENT X DB 78H N1 DB ? N2 DB ?DATA ENDSCODE SEGMENT ASSUME CS:CODE ASSUME DS:DATASTART:MOV AX,DATA MOV DS,AX,MOV AL,X SHR AL,1 JC JISHU MOV AL,X MOV N2,AL JMP EXITJISHU:MOV AL,X MOV N1,ALEXIT: MOV AH,4CH INT 21HCODE ENDS END,5.3 从STR开始存放一字符串，统计串中字符A的个数，存放在RESU字节单元。,DATA SEGMENT STR DB ASAAASAAS CNT EQU $-STR RESU DB ? DATA ENDSCODE SEGMENT ASSUME CS:CODE ASSUME DS:DATASTART: MOV AX,DATA MOV DS,AX MOV CX,CNT MOV BX,0 MOV AX,0,COUNT:CMP STRBX,A JZ A_NO JMP NEXTA_NO: INC AL. ;A个数加1NEXT: INC BX DEC CX JNZ COUNT MOV RESU, AL MOV AH,4CH INT 21HCODE ENDS END START,5.4 从BUF开始存放若干带符号字节数据，将它们相加并将结果（超过一字节范围）存放到字单元SUM中。,5.5 将两个多字节压缩BCD码相加，假定两个压缩BCD码分别从BCD1、BCD2开始存放，结果从BCD3开始存放。,5.6设从STRING开始存放一以为结束标志的字符串，把字符串中的字符分类，数字送入NUM开始的内存区，字母送入CHAR开始的内存区，其它字符存到OTHER开始的内存区。,DATA SEGMENT STRING DB 1$9AaGgzZ# CNT EQU $-STRING-1 NUM DB CNT DUP (?) CHAR DB CNT DUP (?) OTHER DB CNT DUP (?)DATA ENDSCODE SEGMENT ASSUME CS:CODE, DS:DATASTART: MOV AX,DATA MOV DS,AX MOV BP,OFFSET STRING MOV SI,OFFSET NUM MOV DI,OFFSET CHAR MOV BX,OFFSET OTHER,LOP1: MOV AL,DS:BP CMP AL,# JZ EXIT CMP AL,0 JB OTHER1 CMP AL,9 JBE NUM1 CMP AL,A JB OTHER1 CMP AL,Z JBE CHAR1 CMP AL,a JB OTHER1 CMP AL,z JA OTHER1,CHAR1: MOV DI,AL INC DI JMP NEXTNUM1: MOV SI,AL INC SI JMP NEXTOTHER1:MOV BX,AL INC BXNEXT: INC BP JMP LOP1EXIT: MOV AH,4CH INT 21HCODE ENDS END START,5.7 找出首地址为BUF的包含若干个带符号字节数据的数据块中的最小偶数，结果放在RESU字节单元中，并以16进制形式显示在屏幕上。,参考程序1：DATA SEGMENT BUF DB -1,4,-4,23,12 CNT EQU $-BUF RESU DB ? EVEN1 DB CNT DUP(?) DATA ENDSCODE SEGMENT ASSUME CS:CODE, DS:DATASTART:MOV AX,DATA MOV DS,AX,MOV SI,OFFSET BUF MOV DI,OFFSET EVEN1 MOV CX,CNT MOV DX,0LOP1:MOV AL,SI TEST AL,01H JNZ NEXT1 ；奇数转移 MOV DI,AL INC DI INC DX ；DX为偶数个数NEXT1:INC SI LOOP LOP1,DEC DX MOV CX,DX MOV DI,OFFSET EVEN1 MOV AL,DICMP1:INC DI CMP AL,DI JLE NEXT2 MOV AL,DINEXT2:LOOP CMP1 MOV RESU,AL,MOV BL,AL MOV CL,4 SHR AL, CL CMP AL,0AH JB HEX ADD AL,7HEX: ADD AL,30H MOV DL,AL MOV AH,2 INT 21H；输出高位,AND BL,0FH CMP BL,0AH JB HEX1 ADD BL,7HEX1: ADD BL,30H MOV DL,BL MOV AH,2 INT 21H；输出低位 MOV DL,H MOV AH,2 INT 21H ；输出H MOV AH,4CH INT 21HCODE ENDS END START,参考程序2：,DATA SEGMENT BUF DB -1,-2,3,2,-6 CNT EQU $-BUF RESU DB ?DATA ENDSCODE SEGMENT ASSUME CS:CODE ASSUME DS:DATASTART:MOV AX,DATA MOV DS,AX MOV SI,OFFSET BUF MOV CX,CNTLOP1:MOV AL,SI INC SI TEST AL,01H JNZ NEXT1,JMP LOP2NEXT1:DEC CX JNZ LOP1 JMP EXITLOP2: DEC CX JZ NEXT2;找第一个偶数LOP3: MOV BL,SI TEST BL,01H JNZ LOP4 CMP AL,BL JLE LOP4 MOV AL,