Implementing Arithmetic Expressions

R = - (X + (-Y)) + Z
 
 INCLUDE Irvine32.inc
 .data
   prompt1  BYTE  "Calculating the expression: - (X + (-Y)) + Z", 0Dh, 0Ah, 0
   prompt2  BYTE  "Enter the value of X:  ", 0
   prompt3  BYTE  "Enter the value of Y:  ", 0
   prompt4  BYTE  "Enter the value of Z:  ", 0
   prompt5  BYTE  "The result R is  ", 0 
   R  SWORD  ?
   X  SWORD  ?
   Y  SWORD  ?
   Z  SWORD  ?
 .code
 main proc
   call   Clrscr
   mov    edx, OFFSET prompt1     ; Calculating the expression: - (X + (-Y)) + Z
   call   WriteString
   mov    edx, OFFSET prompt2     ; Enter the value of X:
   call   WriteString
   call   ReadInt
   mov    X, ax
   mov    edx, OFFSET prompt3     ; Enter the value of Y:
   call   WriteString
   call   ReadInt
   mov    Y, ax
   mov    edx, OFFSET prompt4     ; Enter the value of Z:
   call   WriteString
   call   ReadInt
   mov    Z, ax
   mov    ax, X                   ; R = - (X + (-Y)) + Z



 

  

   
     
   


     
  		
  
  
     
       
   
   
  
  


   neg    ax   
   add    ax, Z
   mov    R, ax
   mov    edx, OFFSET prompt5     ; The result R is 
   call   WriteString
   movsx  eax, R
   call   WriteInt
   call   Crlf
   call   Crlf
   exit
 main ENDP
 END main
An Execution Example 
 Calculating the expresssion: - (X + (-Y)) + Z
 Enter the value of X:  20 
 Enter the value of Y:  10 
 Enter the value of Z:  -10 
 The result R is  -20

†The italic white text with navy background is entered by users.


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      ― Unknown