比较两个字符串
1. 题目：比较字符串是否相等
2.
要求：写一程序，比较两个字符串String1和String2所含的字符是否相同；若相同则显示’Match’，否则显示’No Match’。
输入两个字符串之后，将串操作所必须的寄存器等参数设置好，然后使用串操作指令进行从头到尾的比较，两个字符串相等的条件是串长度相等且对应的字符相同。
1 ; Example assembly language program --
2 ; Author: karllen
3 ; Date: revised 05/2014
4
5 .386
6 .MODEL FLAT
7
8 ExitProcess PROTO NEAR32 stdcall, dwExitCode:DWORD
9
10 INCLUDE io.h ; header file for input/output
11
12 cr EQU 0dh ; carriage return character
13 Lf EQU 0ah ; line feed
14
15 .STACK 4096 ; reserve 4096-byte stack
16
17 .DATA
18 str1 BYTE 80 DUP(?)
19 str2 BYTE 80 DUP(?)
20 value BYTE 11 DUP(?)
21 length1 DWORD ?
22 length2 DWORD ?
23
24 promot1 BYTE "Please Enter String1",cr,Lf,0
25 promot2 BYTE "Please Enter String2",cr,Lf,0
26 crlf BYTE cr,Lf,0
27
28 answerYes BYTE "Match",cr,Lf,0
29 answerNo BYTE "No Match",cr,Lf,0
30 PUBLIC _start ; make entry point public
31 .CODE ; start of main program code
32 _start:
33 output promot1
34 input str1,80
35 lea eax,str1
36 push eax
37 call strlen
38 add esp,4
39 mov length1,eax
40 dtoa value,eax
41 output value
42 output crlf
43
44 output promot2
45 input str2,80
46 lea eax,str2
47 push eax
48 call strlen
49 add esp,4
50 mov length2,eax
51 dtoa value,eax
52 output value
53 output crlf
54
55 mov edx,length2
56 ;;cmp String1 and String2
57 cmp eax,edx ;如果长度不相等
58 jne endCMP ;则结束
59 ;比较
60 lea esi,str1
61 lea edi,str2
62 mov ecx,length2 ;比较的长度
63 repe cmpsb
64 jz found ;比较成功则跳转
65
66 endCMP:
67 output answerNo
68 jmp endMatch
69 found:
70 output answerYes
71 ;
72 endMatch:
73
74 INVOKE ExitProcess, 0 ; exit with return code 0
75
76 strlen PROC NEAR32
77 push ebp
78 mov ebp, esp
79
80 sub eax, eax
81 mov ebx, [ebp+8]
82 whileChar: cmp BYTE PTR [ebx], 0
83 je endWhileChar
84 inc eax
85 inc ebx
86 jmp whileChar
87 endWhileChar:
88 pop ebp
89 ret
90 strlen ENDP
91 END ; end of source code
时间： 2024-11-05 13:42:34