month.asm

用汇编写的月份天数查询.

.model 	small
.data
	msg		db		'Enter A month(1~12): $'
	msg1	db		0dh,0ah,'$'
	monInfo	db		'Jan$','Feb$','Mar$','Apr$','May$','Jun$','Jul$','Aug$','Sep$','Oct$','Nov$','Dec$'
	month	db		3,?,3 dup(0)
	table	dw		month_1
			dw		month_2
			dw		month_3
			dw		month_4
			dw		month_5
			dw		month_6
			dw		month_7
			dw		month_8
			dw		month_9
			dw		month_10
			dw		month_11
			dw		month_12
.code
start:
	mov	ax,@data
	mov	ds,ax
	mov	es,ax
	
	lea	dx,msg				;显示信息
	mov	ah,09h
	int	21h

	lea	dx,month			;输入月份数
	mov	ah,0ah
	int	21h

	lea	dx,msg1
	mov	ah,09h
	int	21h

	mov	al,month+1			;al放入月份位数
	cmp	al,1				
	ja	double				;月份为两位数
	mov	al,month+2			;月份为一位数
	sub	al,30h
	jmp	follow				
double:
	mov	al,month+3
	sub	al,30h
	add	al,10
follow:
	sub	ah,ah
	dec ax
	shl	ax,1				;ax存月份 
	mov	si,ax
		
	jmp	table[si]
	
month_1:
	lea	dx,monInfo
	jmp	next
month_2:
	lea	dx,monInfo+4
	jmp	next
month_3:
	lea	dx,monInfo+8
	jmp	next
month_4:
	lea	dx,monInfo+12
	jmp	next
month_5:
	lea	dx,monInfo+16
	jmp	next
month_6:
	lea	dx,monInfo+20
	jmp	next
month_7:
	lea	dx,monInfo+24
	jmp	next
month_8:
	lea	dx,monInfo+28
	jmp	next
month_9:
	lea	dx,monInfo+32
	jmp	next
month_10:
	lea	dx,monInfo+36
	jmp	next
month_11:
	lea	dx,monInfo+40
	jmp	next
month_12:
	lea	dx,monInfo+44
	jmp	next
next:
	mov	ah,09h			;输出结果
	int	21h
	
	mov	ax,4c00h		;返回dos
	int	21h
end	start