組語期末上機考
第一題
輸入兩個 32-bit 正整數，輸出其最小公倍數。
Code
TITLE fe1.asm
include Irvine32.inc
.data
prompt1 BYTE "Enter the first number: ", 0
prompt2 BYTE "Enter the second number: ", 0
result BYTE "The least common multiple is: ", 0
newline BYTE 10, 0
.data?
num1 DWORD ?
num2 DWORD ?
.code
main PROC
; Print prompt for first number
mov edx, OFFSET prompt1
call WriteString
; Read first number from user
call ReadInt
mov num1, eax
; Print prompt for second number
mov edx, OFFSET prompt2
call WriteString
; Read second number from user
call ReadInt
mov num2, eax
; Find the greatest common divisor (GCD)
mov eax, num1
mov ebx, num2
call gcd
; Calculate the least common multiple (LCM)
mov ecx, eax
mov eax, num1
mov ebx, num2
mul ebx
div ecx
; Print the result
mov edx, OFFSET result
call WriteString
call WriteInt
; Print a newline
mov edx, OFFSET newline
call WriteString
call Crlf
; Exit the program
exit
main ENDP
gcd PROC
; Euclidean algorithm to find the GCD
cmp eax, ebx
jz done
jb swap
sub eax, ebx
jmp gcd
swap:
xchg eax, ebx
jmp gcd
done:
ret
gcd ENDP
END main
結果
第二題
輸入一個日期，輸出那天星期幾。
Code
TITLE fe2.asm
include Irvine32.inc
.data
prompt BYTE "Please type data in format (yyyy/mm/dd): ", 0
weekday BYTE "The day is ", 0
newline BYTE 10, 0
inputDate BYTE 11 DUP(?) ; 存儲輸入的日期字串
weeks BYTE "Sunday ", 0
BYTE "Monday ", 0
BYTE "Tuesday ", 0
BYTE "Wednesday", 0
BYTE "Thursday ", 0
BYTE "Friday ", 0
BYTE "Saturday ", 0
offsetValue DWORD 10
.code
main PROC
; Print prompt for date
mov edx, OFFSET prompt
call WriteString
; Read date from user
mov ecx, 11 ; Buffer size (including null terminator)
mov edx, OFFSET inputDate
call ReadString
; Extract year, month, and day
mov esi, OFFSET inputDate ; Offset of the input date string
call ParseDate
; Adjust month and year for Zeller's congruence
sub ebx, 3
jz adjust_year
sub ebx, 12
inc eax
adjust_year:
cmp ebx, 0
jl adjust_year
; Calculate Zeller's congruence
mov edx, eax
mov eax, 1
mov ecx, ebx
mov ebx, 2
mov esi, 20
call ZellersCongruence
; Map the weekday to its corresponding name
mov edx, OFFSET weekday
cmp eax, 0
je sunday
cmp eax, 1
je monday
cmp eax, 2
je tuesday
cmp eax, 3
je wednesday
cmp eax, 4
je thursday
cmp eax, 5
je friday
cmp eax, 6
je saturday
sunday:
mov ebx, 0
jmp print_weekday
monday:
mov ebx, 1
jmp print_weekday
tuesday:
mov ebx, 2
jmp print_weekday
wednesday:
mov ebx, 3
jmp print_weekday
thursday:
mov ebx, 4
jmp print_weekday
friday:
mov ebx, 5
jmp print_weekday
saturday:
mov ebx, 6
print_weekday:
mov edx, OFFSET weekday
call WriteString
; Print the weekday
mov esi, OFFSET weeks
mov eax, offsetValue
mul ebx
add esi, eax
mov edx, esi
call WriteString
; Print a newline
mov edx, OFFSET newline
call WriteString
exit
main ENDP
ParseDate PROC
; Parses the input date string in the format "yyyy/mm/dd"
; Input: esi = offset of the input string
; Output: eax = year, ebx = month, ecx = day
movzx eax, byte ptr [esi] ; Extract the first digit of the year (thousands place)
imul eax, eax, 1000
inc esi
movzx ebx, byte ptr [esi] ; Extract the second digit of the year (hundreds place)
imul ebx, ebx, 100
inc esi
movzx edx, byte ptr [esi] ; Extract the third digit of the year (tens place)
imul edx, edx, 10
inc esi
movzx ecx, byte ptr [esi] ; Extract the fourth digit of the year (ones place)
add eax, ebx ; Combine all four digits to form the year
add eax, edx ; Combine the tens and ones place of the month
inc esi
movzx ebx, byte ptr [esi] ; Extract the hundreds place of the month
imul ebx, ebx, 10
inc esi
movzx edx, byte ptr [esi] ; Extract the ones place of the month
add eax, ebx ; Combine the hundreds and tens place to form the month
add eax, edx ; Combine all digits to form the month
add esi, 2 ; Skip the slash (/)
movzx ebx, byte ptr [esi] ; Extract the tens place of the day
imul ebx, ebx, 10
inc esi
movzx edx, byte ptr [esi] ; Extract the ones place of the day
add ecx, ebx ; Combine the tens and ones place to form the day
add ecx, edx ; Combine all digits to form the day
ret
ParseDate ENDP
ZellersCongruence PROC
; Zeller's Congruence algorithm to calculate the weekday
; Inputs: eax = day of the month (1-31), ebx = adjusted month (1-12), ecx = adjusted year, esi = century value (e.g., 20 for 2020)
; Outputs: eax = weekday (0-6, 0 = Saturday, 1 = Sunday, ..., 6 = Friday)
mov edx, eax
mov eax, ecx
mov ecx, ebx
; Zeller's Congruence formula: h = (q + (13*(m+1))/5 + K + K/4 + J/4 - 2*J) mod 7
mov edx, 13
mul ecx ; edx:eax = ecx * 13
add eax, edx ; eax = eax + edx = ecx * 13 + edx
add eax, esi ; eax = eax + esi = ecx * 13 + edx + esi
add eax, ecx ; eax = eax + ecx = ecx * 13 + edx + esi + ecx
shr eax, 2 ; eax = eax / 4 = (ecx * 13 + edx + esi + ecx) / 4
add eax, edx ; eax = eax + edx = (ecx * 13 + edx + esi + ecx) / 4 + edx
shr eax, 2 ; eax = eax / 4 = (ecx * 13 + edx + esi + ecx) / 4 + edx / 4
sub eax, edx ; eax = eax - edx = (ecx * 13 + edx + esi + ecx) / 4 + edx / 4 - edx
add eax, ecx ; eax = eax + ecx = (ecx * 13 + edx + esi + ecx) / 4 + edx / 4 - edx + ecx
and eax, 7 ; eax = eax % 7 = (ecx * 13 + edx + esi + ecx) / 4 + edx / 4 - edx + ecx % 7
ret
ZellersCongruence ENDP
END main
結果
第三題
輸入一個正整數，輸出所有比它小的質數。
Code
TITLE fe3.asm
INCLUDE Irvine32.inc
.data
prompt BYTE "Please type an integer:", 0
output BYTE "Primes smaller than input:", 0
newline BYTE 0DH, 0AH, 0
input DWORD ?
temp DWORD ?
.code
main PROC
mov edx, OFFSET prompt
call WriteString ; 印出提示訊息
call ReadInt
mov input, eax
mov ebx, input
mov ecx, input ; 將輸入的整數儲存到 ecx 寄存器
mov eax, 2 ; eax = 2 (第一個質數)
cmp ecx, eax ; 比較輸入的整數與 2 的大小
jle done ; 如果輸入的整數小於或等於 2，則直接跳出程式
mov edx, OFFSET output
call WriteString ; 印出 "質數：" 字串
mov temp, 0
print_loop:
call WriteInt ; 印出質數
next_number:
inc eax ; 目前的質數加 1
mov temp, eax
cmp eax, input ; 比較目前的質數與輸入的整數的大小
jg done ; 如果目前的質數大於輸入的整數，則跳出迴圈
mov ebx, 2 ; ebx = 2 (除數)
is_prime:
mov edx, 0 ; edx = 0 (除數是否整除的標誌)
div_check:
div ebx ; eax / ebx，商存在 eax，餘數存在 edx
mov eax, temp
cmp edx, 0 ; 判斷是否整除
je next_number ; 如果整除，則不是質數
inc ebx ; 除數加 1
cmp ebx, eax; 比較除數與目前的質數的大小
je print_loop ; 如果除數大於目前的質數，則目前的質數是質數
jmp is_prime ; 目前的質數不是質數，繼續找下一個
done:
call Crlf ; 換行
exit
main ENDP
END main
結果
第四題
寫一個計算機，可以計算輸入運算式結果，支援 + - * / ( )，如 2+4-6*2 = -6。
Code
結果
第五題
修改 TSR 的 Clock2.asm 或 Clock3.asm 不出現時間 改出現 NCYUCSIE 開始由 N 出現後出現 C 再來出現 Y 一個字母一個字母出現 到 E 後又從 N 開始。