Question

Write an assembly language program with a loop and indexed addressing that calculates the sum of all the gaps between successive array elements. The array elements are DWORDs, sequenced in non-decreasing order. For example, the array [0, 2, 5, 9, 10] has gaps 2, 3, 4, and 1, whose sum equals 10.

Answer 1

Answer:

Description: Write a MASM 32bit program with a loop and indexed addressing that calculates the sum of all thegaps between successive array elements. The array elements are doublewords, sequenced in nondecreasing order.

;Include Irvine32.inc file used with link library for 32 bit applications

.386

.model flat,stdcall

.stack 4096

ExitProcess proto,dwExitCode:dword

INCLUDE Irvine32.inc

.data

myArray DWORD 0,2,5,9,10

arrSize = ($-myArray)/TYPE myArray

gapArr DWORD arrSize-1 DUP(?)

sum DWORD ?

.code

main PROC

;Call the procedure

call Clrscr

;Initialize ESI pointer

mov esi, 0

mov ecx, arrSize

dec ecx

L1:

mov eax, myArray[esi+4]

sub eax, myArray[esi]

mov gapArr[esi], eax

inc esi

loop L1

;Calculate the sum of gaps between array elements

mov sum, 0

mov esi, 0

mov ecx, arrSize

dec ecx

;  move gapArr[esi] to a temporary register and then add that register value to sum

L2:

mov edx, gapArr[esi]  

add sum, edx

inc esi

loop L2

       INVOKE ExitProcess,0

main ENDP

END main

Explanation: