我的程序应该采用两个整数和一个运算符（除法、乘法、加法、减法）。如有必要，它会从那里计算答案和余数。
之后，它应该提示用户是否要进行另一个计算，使用 (y/n) 选项。如果是，它重新循环，如果不是，程序退出。出于某种原因，它不允许我输入 (y/n) 的选项，而只是跳过我的输入并直接终止。这是我的代码。（对不起初学者）
在我输入运算符之前，我还会收到“未知错误代码 45”（弹出窗口？）。
# SPIM Calculator
# Computer Organization
.data
prompt: .asciiz "Welcome to SPIM Calculator 1.0!\n"
first_prompt: .asciiz "Enter the first number: "
second_prompt: .asciiz "Enter the second number: "
operator: .asciiz "Enter the operation (+, -, *, /), then press enter key: "
error_message: .asciiz "\n\nArgument is invalid. Try again!\n\n"
sp: .asciiz " "
nl: .asciiz "\n"
eq: .asciiz " = "
parl: .asciiz "("
parr: .asciiz ")"
again_prompt: .asciiz "\nWould you like to do another calculation? ( y / n ) "
ended_message: .asciiz "\nCalculations complete."
.globl main
.text
main:
#initialize
li $s0, 10
# Prompt welcome
li $v0, 4 # print string value 4
la $a0, prompt # loads address from memory
syscall
loop:
# display prompt for q.1
li $v0, 4 # loads value 4 into register v0 which is op code for print string
la $a0, first_prompt # loads address from memory, stores it in argument register
syscall # reads register $v0 for op code, sees 4 and prints string located in $a0
# get input
li $v0, 5 # load op code for getting an integer from user into register $v0
syscall # reads it and puts in $t0
move $s0, $v0 # $s0 saves it
# display prompt for q.2
li $v0, 4 # loads value 4 into register v0 which is op code for print string
la $a0, second_prompt # loads address from memory, stores it in argument register
syscall # reads register $v0 for op code, sees 4 and prints string located in $a0
# get input
li $v0, 5 # load op code for getting an integer from user into register $v0
syscall # reads it and puts in $v0
move $s1, $v0 # $s1 saves it
# display prompt for q.3
li $v0, 4 # loads value 4 into register v0 which is op code for print string
la $a0, operator # loads address from memory, stores it in argument register
syscall # reads register $v0 for op code, sees 4 and prints string located in $a0
#get input
li $v0, 12 # load op code for getting an symbol from user into register $v0
syscall # reads it and puts in $t0
move $s2, $v0 # $s0 saves it
# check symbol and use if statements to go to correct part in program
beq $s2, '*', Multiplication
beq $s2, '/', Division
beq $s2, '-', Subtraction
beq $s2, '+', Addition
# in case it is none of these
li $v0, 4 # print string value 4
la $a0, error_message # loads address from memory
syscall
Multiplication:
# perform multiplication
mult $s0, $s1
mflo $s3 # moves product to $s3
syscall
jr Print
Division:
# perform division
divu $s0, $s1
mflo $s3 # moves quotient to $s3
mfhi $s4 # move remainder to $s4
syscall
jr Print
Subtraction:
# perform subtraction
sub $s3, $s0, $s1 # moves result to $s3
syscall
jr Print
Addition:
# perform addition
add $s3, $s0, $s1 # moves result to $s3
syscall
jr Print
Print:
# print new line
li $v0, 4
la $a0, nl
syscall
# print first number
li $v0, 1 # print int
move $a0, $s0
syscall
# print space
li $v0, 4
la $a0, sp
syscall
# print operator
li $v0, 11 # print operator
move $a0, $s2
syscall
# print space
li $v0, 4
la $a0, sp
syscall
# print second number
li $v0, 1 # print int
move $a0, $s1
syscall
# print equals
li $v0, 4
la $a0, eq
syscall
# jump to printing specifically for division
beq $s2, '/', Division_Print
# print result
li $v0, 1 # print int
move $a0, $s3
syscall
# print new line
li $v0, 4
la $a0, nl
syscall
jr Again_Prompt
Division_Print:
# print quotient
li $v0, 1 # print int
move $a0, $s3
syscall
# print space
li $v0, 4
la $a0, sp
syscall
# print left parenthesis
li $v0, 4
la $a0, parl
syscall
# print remainder
li $v0, 1 # print int
move $a0, $s4
syscall
# print right parenthesis
li $v0, 4
la $a0, parr
syscall
# print new line
li $v0, 4
la $a0, nl
syscall
jr Again_Prompt
Again_Prompt:
# display prompt
li $v0, 4 # loads value 4 into register v0 which is op code for print string
la $a0, again_prompt # loads address from memory, stores it in argument register
syscall # reads register $v0 for op code, sees 4 and prints string located in $a0
# get input
li $v0, 12 # load op code for getting a character from user into register $v0
syscall # reads it and puts in $t0
move $s6, $v0 # $s6 saves it
# print new line
li $v0, 4
la $a0, nl
syscall
# determine whether or not to do another calculation
beq $s6, 'y', loop
beq $s6, 'n', Terminate
Terminate:
li $v0, 4 # loads value 4 into register v0 which is op code for print string
la $a0, ended_message # loads address from memory, stores it in argument register
syscall # reads register $v0 for op code, sees 4 and prints string located in $a0
jr $ra