初めて来ました、大学生です。アセンブリ言語を使用して簡単なプログラムを作成しました。そして、ループメソッドを使用して、投稿したプログラムの下で行うこととほぼ同じことを実行できるかどうか疑問に思っています。また、MSNメッセンジャーで話せる人を見つけたいので、すぐに質問できます.（可能であれば）ありがとうございます.
.MODEL small
.STACK 400h
.data
prompt db 10,13,'Please enter a 3 digit number, example 100:',10,13,'$' ;10,13 cause to go to next line
first_digit db 0d
second_digit db 0d
third_digit db 0d
Not_prime db 10,13,'This number is not prime!',10,13,'$'
prime db 10,13,'This number is prime!',10,13,'$'
question db 10,13,'Do you want to contine Y/N $'
counter dw 0d
number dw 0d
half dw ?
.code
Start:
mov ax, @data ;establish access to the data segment
mov ds, ax
mov number, 0d
LetsRoll:
mov dx, offset prompt ; print the string (please enter a 3 digit...)
mov ah, 9h
int 21h ;execute
;read FIRST DIGIT
mov ah, 1d ;bios code for read a keystroke
int 21h ;call bios, it is understood that the ascii code will be returned in al
mov first_digit, al ;may as well save a copy
sub al, 30h ;Convert code to an actual integer
cbw ;CONVERT BYTE TO WORD. This takes whatever number is in al and
;extends it to ax, doubling its size from 8 bits to 16 bits
;The first digit now occupies all of ax as an integer
mov cx, 100d ;This is so we can calculate 100*1st digit +10*2nd digit + 3rd digit
mul cx ;start to accumulate the 3 digit number in the variable imul cx
;it is understood that the other operand is ax
;AND that the result will use both dx::ax
;but we understand that dx will contain only leading zeros
add number, ax ;save
;variable <number> now contains 1st digit * 10
;----------------------------------------------------------------------
;read SECOND DIGIT, multiply by 10 and add in
mov ah, 1d ;bios code for read a keystroke
int 21h ;call bios, it is understood that the ascii code will be returned in al
mov second_digit, al ;may as well save a copy
sub al, 30h ;Convert code to an actual integer
cbw ;CONVERT BYTE TO WORD. This takes whatever number is in al and
;extends it to ax, boubling its size from 8 bits to 16 bits
;The first digit now occupies all of ax as an integer
mov cx, 10d ;continue to accumulate the 3 digit number in the variable
mul cx ;it is understood that the other operand is ax, containing first digit
;AND that the result will use both dx::ax
;but we understand that dx will contain only leading zeros. Ignore them
add number, ax ;save -- nearly finished
;variable <number> now contains 1st digit * 100 + second digit * 10
;----------------------------------------------------------------------
;read THIRD DIGIT, add it in (no multiplication this time)
mov ah, 1d ;bios code for read a keystroke
int 21h ;call bios, it is understood that the ascii code will be returned in al
mov third_digit, al ;may as well save a copy
sub al, 30h ;Convert code to an actual integer
cbw ;CONVERT BYTE TO WORD. This takes whatever number is in al and
;extends it to ax, boubling its size from 8 bits to 16 bits
;The first digit now occupies all of ax as an integer
add number, ax ;Both my variable number and ax are 16 bits, so equal size
mov ax, number ;copy contents of number to ax
mov cx, 2h
div cx ;Divide by cx
mov half, ax ;copy the contents of ax to half
mov cx, 2h;
mov ax, number; ;copy numbers to ax
xor dx, dx ;flush dx
jmp prime_check ;jump to prime check
print_question:
mov dx, offset question ;print string (do you want to continue Y/N?)
mov ah, 9h
int 21h ;execute
mov ah, 1h
int 21h ;execute
cmp al, 4eh ;compare
je Exit ;jump to exit
cmp al, 6eh ;compare
je Exit ;jump to exit
cmp al, 59h ;compare
je Start ;jump to start
cmp al, 79h ;compare
je Start ;jump to start
prime_check:
div cx; ;Divide by cx
cmp dx, 0h ;reset the value of dx
je print_not_prime ;jump to not prime
xor dx, dx; ;flush dx
mov ax, number ;copy the contents of number to ax
cmp cx, half ;compare half with cx
je print_prime ;jump to print prime section
inc cx; ;increment cx by one
jmp prime_check ;repeat the prime check
print_prime:
mov dx, offset prime ;print string (this number is prime!)
mov ah, 9h
int 21h ;execute
jmp print_question ;jumps to question (do you want to continue Y/N?) this is for repeat
print_not_prime:
mov dx, offset Not_prime ;print string (this number is not prime!)
mov ah, 9h
int 21h ;execute
jmp print_question ;jumps to question (do you want to continue Y/N?) this is for repeat
Exit:
mov ah, 4ch
int 21h ;execute exit
END Start