shows two arrays used by one program, both of which are set during the iteration through the for loop. Array a is locally defined, and array b is globally defined. These definitions will impact the assembly code.

shows the assembly code for .

00401006        mov     [ebp+var_18], 0 0040100D        jmp     short loc_401018 0040100F loc_40100F: 0040100F        mov     eax, [ebp+var_18] 00401012        add     eax, 1 00401015        mov     [ebp+var_18], eax 00401018 loc_401018: 00401018        cmp     [ebp+var_18], 5 0040101C        jge     short loc_401037 0040101E        mov     ecx, [ebp+var_18] 00401021        mov     edx, [ebp+var_18] 00401024        mov     [ebp+ecx*4+var_14], edx ❶ 00401028        mov     eax, [ebp+var_18] 0040102B        mov     ecx, [ebp+var_18] 0040102E        mov     dword_40A000[ecx*4], eax ❷ 00401035        jmp     short loc_40100F

In this listing, the base address of array b corresponds to dword_40A000, and the base address of array a corresponds to var_14. Since these are both arrays of integers, each element is of size 4, although the instructions at ❶ and ❷ differ for accessing the two arrays. In both cases, ecx is used as the index, which is multiplied by 4 to account for the size of the elements. The resulting value is added to the base address of the array to access the proper array element.

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