data segment    ;定義數(shù)據(jù)段
    infon db 0dh,0ah,'Please input a year: $'
    Y db 0dh,0ah,'This is a leap year! $'
    N db 0dh,0ah,'This is not a leap year! $'
    w dw 0
    buf db 8
        db ?
        db 8 dup(?)
data ends

stack segment stack
    db 200 dup(0)
stack ends

code segment
          assume ds:data,ss:stack,cs:code
    start:mov ax,data
          mov ds,ax
          
          lea dx,infon  ;在屏幕上顯示提示信息
          mov ah,9
          int 21h

          lea dx,buf    ;從鍵盤(pán)輸入年份字符串
          mov ah,10
          int 21h
          
          mov cl, [buf+1]
          lea di,buf+2
          call datacate
          call ifyears
          jc a1
          
          lea dx,n
          mov ah,9
          int 21h
          jmp exit
    a1:   lea dx,y
          mov ah,9
          int 21h
    exit: mov ah,4ch
          int 21h
       
 

 datacate proc near；
          push cx;                                                       
          dec cx
          lea si,buf+2
     tt1: inc si
          loop tt1
          ;lea si,cx[di]
          pop cx
     
      
          mov dh,30h
          mov bl,10
          mov ax,1
      l1: push ax
          sub  byte ptr  [si],dh
          mul  byte ptr [si]
          add w,ax
          pop ax
          mul bl
          dec si
          loop l1
          ret
 datacate endp


   ifyears proc near
           push  bx
           push  cx
           push  dx
           mov ax,w
           mov   cx,ax
           mov  dx,0
           mov  bx,4
           div  bx
           cmp  dx,0
           jnz  lab1
           mov   ax,cx
           mov  bx,100
           div  bx
           cmp dx,0
           jnz  lab2
           mov  ax,cx
           mov bx,400
           div  bx
           cmp  dx,0
           jz  lab2
     lab1: clc
           jmp lab3
     lab2: stc
     lab3: pop  dx
           pop  cx
           pop  bx
           ret
   ifyears endp
code ends
   end start