比较长度相等的两个字符串相同和不同字母个数

Posted 2021-02-19 dzcixy

DATAS SEGMENT
    STR1 DB ‘ABCD$‘ 
    STR2 DB ‘ABCD$‘
    len equ $-str2
    ;len DW str2-str1
    match  DB ‘EQU:‘,0DH,0AH,‘$‘
    nomatch DB ‘NOEQU:‘, 0DH, 0AH, ‘$‘
    change DB  0DH, 0AH, ‘$‘
    E DB ‘0$‘
	NTE DB ‘0$‘
DATAS ENDS

STACKS SEGMENT
    ;此处输入堆栈段代码
STACKS ENDS

CODES SEGMENT
    ASSUME CS:CODES,DS:DATAS,SS:STACKS
START:
    MOV AX,DATAS
    MOV DS,AX
    
    mov si, 0
    mov cx, len
    dec cx
loop1:
	mov al, STR1[si]
	mov ah, STR2[si]
	cmp al, ah
	jne l1
	inc   E
	jmp l2
	l1:
		inc  NTE
	l2: 
		inc si
	loop loop1
	
	
	LEA dx,STR1;显示STR1和STR2两个字符串
 	MOV ah,09h
 	INT 21H
 	LEA dx,change
 	MOV ah,09h
 	INT 21H
 	LEA dx,STR2
 	MOV ah,09h
 	INT 21H
 	LEA dx,change
 	MOV ah,09h
 	INT 21H
	
	
	LEA dx,match
 	MOV ah,09h
 	INT 21H
	
	lea dx, E
	mov ah, 09h
	int 21h
	
	LEA dx,change
 	MOV ah,09h
 	INT 21H
	
	LEA dx,nomatch
 	MOV ah,09h
 	INT 21H
 	
 	lea dx, NTE
	mov ah, 09h
	int 21h

	
    MOV AH,4CH
    INT 21H
CODES ENDS
    END START

　　$代表的是当前的地址，所以当前地址减去str2的地址，就是str2的长度，同理len equ $-str1也是一样的。