The assembly language inputs a string from the keyboard (the string length is not greater than 80) and outputs the number of non-letter characters in the string in decimal notation (not a to z or A to Z)

(1) Input a string from the keyboard (the string length is not more than 80).
(2) Output the number of non-alphabetic characters in the string in decimal notation (not a to z or A to Z).
(3) Output the original character string and make non-alphabetic characters flashing.
(4) Find the character with the largest ASCII code value in the string, and display it in red in the string.
(5) The input of the string and the output of the result must have necessary prompts, and the prompts are on a line.
(6) To use the subroutine.

data segment
   hintinput db "please input a string:$"
   hintoutput1 db "The number of non-alphabetic characters:$";输出非字母字符的个数
   hintoutput2 db "flashes non-alphabetic characters:$";输出原字符串并闪烁
   hintoutput3 db "The character with the largest ASCII value in a string:$";ascill最大字符
           buf db 200
	           db ?
	           db 200 dup(?)
         count db 0
crlf db 0ah,0dh,'$'
data ends
stack segment stack
   string db 500 dup(?)
stack ends
extra segment   ;定义附加段

extra ends
codes segment
	assume cs:codes,ds:data,ss:stack,es:extra
	main proc far
start:
mov ax,data  ;分别将数据段，堆栈段，附加段送入代码段
  mov ds,ax
  mov ax,stack
  mov ss,ax
  mov ax,extra
  mov es,ax
;---------------------------输入字符串提示语并进行回车换行
  lea dx,hintinput ;输入提示语
  mov ah,9;输出功能入口在dx
  int 21h
  lea dx,crlf;输入提示语后，回车换行
  mov ah,09
  int 21h
;---------------------------通过a号功能进行字符串输入操作并回车换行
  mov ah,0ah;输入功能入口在dx
  lea dx,buf
  int 21h

  lea dx,crlf        ;输入后回车换行
  mov ah,9
  int 21h
;------------------------------------首先用cl储存字符串长度，si源变址寄存器指向串真正开始的地方
  mov cl,buf+1;cl中放置实际字符串长度
                               
  lea si,buf+2;si放置字符串首地址
;------------------------------------首先输出提示语回车换行，以十进制输出字符串中非字母字符的个数（不是a to z或 A to Z）。
  
  call print1
;-------------------------------------- 
  call print2
;---------=----------------------------
  call print3
;--------------------------------------
  mov ah,4ch
  int 21h
  main endp
  
print1 proc near                         ;-----------------子程序一入口
  push cx
  push si
  lea dx,hintoutput1 ;输出提示语
  mov ah,09h;输出功能入口在dx
  int 21h
  lea dx,crlf;输入提示语后，回车换行
  mov ah,09
  int 21h
  mov dl,0 ;用dl来计数，统计符串中非字母字符的个数
  L0:
  mov al,[si]
  cmp al,'A'      
  jb L1           ;如果字符<'A',跳转到L1
  cmp al,'Z'      
  jbe L2           ;如果字符<='Z',跳转到L2
  cmp al,'a'      
  jb L1           ;如果字符<'a',跳转到L1
  cmp al,'z'      
  jbe L2           ;如果字符<='Z',跳转到L2

L1:
  inc dl     ;计数器加1
L2:
  inc si
  dec cl
  jnz L0
;----------------------------------输出非字母字符的个数dl

  cmp dl,9h
  jbe L             ;如果非字母个数小于10，则直接加30输出
  mov dh,0           ;否则把dx存入ax中
  mov ax,dx
  mov bl,10               ;ax除以10后，ah作为商
  div bl                              ;al作为余数
  mov dl,al
  mov ch,al           ;防止ah中的商被02h冲掉，先把商转移到ch中
  add dl,30h            ;先输出商，再输出余数，就是10进制了
  mov ah,02h
  int 21h

  mov dl,ch
L:
  add dl,30h
  mov ah,02h
  int 21h
  lea dx,crlf     ;输出后，回车换行
  mov ah,09
  int 21h
  pop si
  pop cx
  ret
  
print2 proc near
  lea dx,hintoutput2 ;输出提示语
  mov ah,09h         ;输出功能入口在dx
  int 21h
  lea dx,crlf        ;输入提示语后，回车换行
  mov ah,09h
  int 21h
  push cx
  push si
  cld                ;方向标志位df清零
  
L3: 
  push cx 
  lodsb            ;从字符串串中取数据至al
  cmp al,'A'      
  jb L4            ;如果字符<'A',跳转到L4
  cmp al,'Z'      
  jbe L5           ;如果字符<='Z',跳转到L5
  cmp al,'a'      
  jb L4            ;如果字符<'a',跳转到L4
  cmp al,'z'      
  jbe L5           ;如果字符<='Z',跳转到L5
L4:                ;如果不是字母，则进行闪烁输出
   mov bl,10000111b  ;bl属性闪烁输出
   mov bh,0        ;显示页为0
   mov cx,1        ;显示字符为1个
   mov ah,09h
   int 10h         ;输出bl属性的字符串
   mov ah,03h
   int 10h         ;读光标位置
   inc dl          ;输出列+1
   mov ah,02h
   int 10h         ;置光标位置
   jmp L6
L5:
   mov bl,00000111b   ;bl属性为平常输出
   mov bh,0            ;显示页为0
   mov cx,1           ;显示字符个数为1个
   mov ah,09h
   int 10h             ;输出属性为bl的字符
   mov ah,03h
   int 10h             ;读光标位置
   inc dl              ;输出列+1
   mov ah,02h
   int 10h             ;置光标位置
L6:
  pop cx
  loop L3
  
  lea dx,crlf           ;输入提示语后，回车换行
  mov ah,09
  int 21h
  pop si
  pop cx
  ret
print3 proc near
  lea dx,hintoutput3  ;输出提示语
  mov ah,09h          ;输出功能入口在dx
  int 21h
  lea dx,crlf         ;输入提示语后，回车换行
  mov ah,09
  int 21h
  push cx
  push si
            ;count用来存放ascill最大的字符
L7:   
  mov al,[si]
  cmp al,count       ;比较al和count的大小，如果al>count，则令al=count
  jbe L8
  mov count,al        
L8:  
  inc si
  dec cl
  jnz L7
  pop si
  pop cx
  cld
 L9: 
  push cx 
  lodsb               ;从串中取数据至al
  cmp al,count      
  jz L11           ;如果字符==ascill码最大字符
L10:                
   mov bl,00000111b   ;bl属性正常输出
   mov bh,0           ;显示页为0
   mov cx,1           ;显示字符为1个
   mov ah,09h
   int 10h            ;输出bl属性的字符串
   mov ah,03h
   int 10h             ;读光标位置
   inc dl             ;输出列+1
   mov ah,02h
   int 10h            ;置光标位置
   jmp L12
L11:
   mov bl,00000100b   ;bl属性为红色输出
   mov bh,0           ;显示页为0
   mov cx,1           ;显示字符个数为1个
   mov ah,09h
   int 10h            ;输出属性为bl的字符
   mov ah,03h
   int 10h            ;读光标位置
   inc dl              ;输出列+1
   mov ah,02h
   int 10h            ;置光标位置
L12:
  pop cx
  loop L9
  lea dx,crlf        ;输出后，回车换行
  mov ah,09
  int 21h
  
  ret
codes ends
end start
;----------------------2020年5月18日14:29:33----------------

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