Loop program design experiment

 

1. count the number of negative elements in a font Array

. 486

Data Segment

Array DW 54,-1050,-6800, 0, 853 ,-

Count equ $-array; space occupied by statistics

Result DW?

Data ends

Code segment

Assume Cs: code, DS: Data

Start:

MoV ax, Data

MoV ds, ax

MoV Si, offset array; pointer Initialization

MoV CX, count/2; the number of statistical data is stored in CX

ClD

MoV dx, 0

LL: lodsw; count to ax

BT ax, 15

JNC next; determine whether it is a negative number

Inc dx; counter plus 1

Next: loop LL

 

MoV result, DX

MoV ah, 4ch

Int 21 h

Code ends

End start

2. Sorting

Data Segment

Block dB 22 h, 55 h, 11 h, 78 h; N 4

Data ends

Code segment

Assume Cs: code, DS: Data

Start:

MoV ax, Data

MoV ds, ax

Lea BX, block; External Loop pointer Initialization

MoV CX, 3; initialize the External Loop counter

Lp1: mov Si, BX; Inner Loop pointer Initialization

MoV dx, CX; inner cycle counter Initialization

MoV Al, [Si]

Lp2: CMP Al, [Si + 1]

Jge lp3

Xchg Al, [Si + 1]

Lp3: Inc Si; modify the inner loop pointer

Dec DX

Jnz lp2

MoV [BX], Al; large number

Inc bx; modify the inner loop pointer

Loop lp1

MoV ah, 4ch

Int 21 h

Code ends

End start

3. Check and count data segmentstrn dB 'hlfhal $ 'count DB? Data endscode segment assume Cs: code, DS: datastart: mov ax, data mov ds, ax mov DL, 0; counter clearing Lea Si, strn; pointer initialization LL: lodsb; read a number, Si moves CMP Al, '$'; to determine whether to end je exit; when an end character exits JP ll; no need to verify the conversion to another or Al, 80 h; add the verification bit mov [SI-1], Al; Save the verified value to INC dl; Add 1 JMP ll Exit: mov count, DL to the counter; add DL to the result, 30 h mov ah, 02 h int 21 h mov ah, 4ch int 21 H code ends end start4. find

Data Segment

First DB 12 h, 44 h, 65 h, 3 h, 0 h

N dw?

Data ends

Code segment

Assume Cs: code, DS: data, ES: Data

Start:

MoV ax, Data

MoV ds, ax

MoV es, ax

MoV dx, 0; counters cleared

MoV CX, 5; set the number of cycles

Lea Si, first; pointer Initialization

LL: mov Al, [Si]; fetch number

INC Si; Modify pointer

CMP Al, 0; compared with 0

Je exit; exit

Inc dx; counter plus 1

Loop LL

Exit: mov N, DX; save result

MoV ah, 4ch

Int 21 h

Code ends

End start