Question

Use a loop with indirect or indexed addressing to reverse the elements of the integer array in place. Do not copy the elements to any other array. Use the SIZEOF, TYPEOF, and LENGHTOF operators to make the program as flexible as possible if the array size and type should be changed in the future. Optionally, you may display the modified array by calling the DumpMem method from the Irvine32 library.

Answer 1

Answer:

INCLUDE Irvine32.inc

.data

      ;declare and initialize an array

      array1 DWORD 10d,20d,30d,40d,50d,60d,70d,80d,90d

.code

main PROC

      ;assign esi value as 0

      mov esi,0

      ;find the size of array

      mov edi, (SIZEOF array1-TYPE array1)

      ;find the length of the array

      ;divide the length by 2 and assign to ecx

      mov ecx, LENGTHOF array1/2

;iterate a loop to reverse the array elements

L1:

      ;move the value of array at esi

      mov eax, array1[esi]

      ;exchange the values eax and value of array at edi

      xchg eax, array1[edi]

      ;move the eax value into the array at esi

      mov array1[esi], eax

      ;increment the value of esi

      add esi, TYPE array1

      ;decrement the value of edi

      sub edi, TYPE array1

      loop L1

;The below code is used to print

;the values of array after reversed.

      ;get the length of the array

      mov ecx, LENGTHOF array1

      ;get the address

      mov esi, OFFSET array1

L2:

      mov eax, [esi]

      ;print the value use either WriteDec or DumpMems

      ;call WriteDec

      ;call crlf

      call DumpMem

      ;increment the esi value

      add esi, TYPE array1

      LOOP L2

exit

main ENDP

END main