北京邮电大学危机原理实验四 子程序设计

一.实验目的:
     1.进一步掌握子程序设计方法;
     2.进一步掌握基本的 DOS 功能调用.

二.实验内容:
     1.从键盘上输入某班学生的某科目成绩.输入按学生的学号由小到大的顺序输入.
     2.统计检查每个学生的名次.
     3.将统计结果在屏幕上显示.
     4.为便于观察,输入学生数目不宜太多,以不超过一屏为宜.输出应便于阅读.尽可
  能考虑美观.
     5.输入要有检错手段.
源程序:

DATA SEGMENT
BUFFER DB 100
       DB 0
       DB 100 DUP (0)
COUNT  DB 0
COUNT1 DB 1
COUNT2 DB 0
COUNT3 DB 1
STRING1 DB 'NUM  RANK  SCORE',0DH,0AH,'$'
STRING2 DB '   ','$'
RANK    DB 100 DUP (?)
MUN     DB 100 DUP (?)
SCORE   DB 100 DUP (?)
DATA ENDS
STACK SEGMENT STACK 'STACK'
      DB 100 DUP (?)
STACK ENDS
CODE  SEGMENT
      ASSUME CS:CODE,DS:DATA,SS:STACK,ES:DATA

MAIN: MOV AX,DATA
      MOV DS,AX
      CALL INPUT
      CALL HH
      CALL CHANGE
      CALL PAIXU
      CALL HH
      CALL OUTPUT
      MOV  AX,4C00H
      INT  21H
     
HH PROC
    MOV AH,02H
    MOV DL,0DH
    INT 21H
    MOV AH,02H
    MOV DL,0AH
    INT 21H
    RET
HH  ENDP

INPUT PROC
      MOV DX,SEG BUFFER
      MOV DS,DX
      MOV DX,OFFSET BUFFER
      MOV AH,0AH
      INT 21H
      RET
INPUT ENDP

CHANGE PROC
      LEA BX,BUFFER
      LEA DI,SCORE
      LEA SI,MUN
      MOV CH,1
CH1:  MOV AL,[BX+2]
      CMP AL,'!'
      JZ  A
      CMP AL,','
      JZ  B
      SUB AL,30H
      ADD AL,AL
      MOV DH,AL
      MOV CL,2
      SHL AL,CL
      ADD AL,DH
      MOV AH,[BX+3]
      SUB AH,30H
      ADD AL,AH
      MOV [DI],AL
      MOV [SI],CH
      INC SI
      INC CH
      INC DI
      INC BX
      INC BX
      JMP CH1
B:    INC BX
      JMP CH1
A:    NOP
      RET
CHANGE ENDP
     
PAIXU PROC   ;假排序,只是获得每个成绩的地址
      SUB CH,1
      MOV AL,CH
      ADD AL,30H
      MOV AH,02H
      MOV DL,AL
      INT 21H
      MOV COUNT,CH
      MOV COUNT2,CH
      LEA SI,SCORE
      LEA BX,RANK
D:    LEA DI,SCORE
      MOV AL,[SI]
E:    MOV AH,[DI]
      CMP AH,AL
      JBE C
      INC COUNT1
      INC DI
      DEC COUNT
      JNZ E
F:    INC SI
      MOV COUNT,CH
      MOV DL,COUNT1
      MOV [BX],DL
      INC BX
      MOV DL,1
      MOV COUNT1,DL
      DEC COUNT2
      JNZ D
      JMP G
C:    INC DI
      DEC COUNT
      JNZ E
      JMP F
G:    NOP
      RET
PAIXU ENDP

OUTPUT PROC ;输出顺序为,number,score,rank
      LEA SI,RANK
      LEA DI,SCORE
      MOV AH,09H
      MOV DX,SEG STRING1
      MOV DS,DX
      MOV DX,OFFSET STRING1
      INT 21H
H:    CALL KONGGE
      MOV AH,02H
      MOV AL,COUNT3
      ADD AL,30H
      MOV DL,AL
      INT 21H
      INC COUNT3
      CALL KONGGE
      MOV AL,[SI]
      ADD AL,30H
      MOV AH,02H
      MOV DL,AL
      INT 21H
      CALL KONGGE
      MOV AL,[DI]
      CBW
      MOV BL,10
      DIV BL
      MOV BH,AH
      ADD AL,30H
      MOV AH,02H       
      MOV DL,AL
      INT 21H
      MOV AL,BH
      ADD AL,30H
      MOV AH,02H
      MOV DL,AL
      INT 21H
      CALL HH
      INC SI
      INC DI
      DEC CH
      JNE H
      JMP J     
KONGGE:   MOV AH,09H
          MOV DX,SEG STRING2
          MOV DS,DX
          MOV DX,OFFSET STRING2
          INT 21H
          RET
J:    NOP
      RET
OUTPUT ENDP

CODE ENDS
     END MAIN