Hello Can Anybody help with my C program

[crisp pollen]

When your question is answered use !solved to mark the question as resolved.

Remember to ask specific questions, provide necessary details, and reduce your question to its simplest form. For tips on how to ask a good question use !howto ask.

[scenic swallow]

Wdym by "does not work"?

[modern pendant]

If I put in the numbers like 99+32=, than nothing happens

[scenic swallow]

I mean first of all if your input is 33 + 22 / 20 = then you don't have 4 numbers and 4 operator like your code asks you to input

If I input e.g. 33 + 22 + 20 + 20 = then I get the outcome 75 which is correct

*incorrect

[modern pendant]

Oh so its actually a working code?

[scenic swallow]

No, just realized that 33 + 22 + 20 + 20 doesn't add up to 75 😅

Also apparently 75 is always the output, regardless of what operators and operands you input

[modern pendant]

why is that?

[scenic swallow]

Idk, but your code is really weird in that you somehow try to account for precedence but then don't really care about it, e.g. if the first operator is a + then you perform that + on the first and second number, regardless of if the second operand is a e.g. a * which would mean you'd need to wait for the 2nd * 3rd operator to add that multiplied value to the first_num rather than what you're doing

In general your code has a lot of duplicate code and is very hard to extend/fix stuff in because you have so many if/else if/else stuffs and so many different variables

[modern pendant]

Can you help plz.. I have to get this done within a hour and a half ...

The a lot of variables come from the instruction which the teacher gave.. I have to follow it all

[scenic swallow]

I mean I can help you to get onto the correct path but really to do this while staying sane we basically have to scratch your entire code.

Also I'm not writing the code for you and neither is anyone here.
There's a nice saying

Your lack of planning is not my emergency

OH, and I didn't even read the instructions, yet.
Just a quick skim and nevermind, you apparently really do need to do it cursed like that and don't need to scratch your entire code.
Anyways, I'll be out for a joint and then read through the assignment.

[limber adder]

this assignment seems a bit too challenging for beginners honestly imho; best way to do it would be recursive descent parsing but by no means that's a "beginner" topic 🙃

[scenic swallow]

Does it seem too challenging?
I mean they're given basically the entire algorithm + they're restricted to a fixed amount of numbers and operands

Also we don't even know from what week that homework is.
I'd say it's okay for like week 3

Maybe even week 2

[limber adder]

shoot jumped the gun sorry;

guess what I meant more is that parsing stuff in general can get difficult fast esp. in C land 🙃

[scenic swallow]

I say that because the concepts required are really simple:

• individual variables rather than any data structure(s)
• only if/else, no loops
• how to read in the input is already given, all you need to do is parse the numbers and operands

[limber adder]

interesting I see

[scenic swallow]

*Oh yeah, also when I say "week 2" I mean week 2 of uni.
If OP is still in school then that'd be more like week 8 or so

I had Java in school for 2.5 years (last semester of 10th, then 11th and 12th grade)
In my mandatory 1st semester uni Java course we surpassed my entire Java knowledge I had from school in week 7 or 8

[modern pendant]

cool

[topaz mulch]

did you get your code from chatgpt?

cuz it kinda looks like it lmao

[modern pendant]

wait how did you know is there a ai kind of style in programming too like in writing?

[limber adder]

yea at my uni using code directly from chatgpt is bona fide academic misconduct 🙃

[modern pendant]

But it stil doesnt work

[limber adder]

cuz chatgpt is free for everyone probably 😂

[topaz mulch]

i would imagine so

[topaz mulch]

idk it just looks a bit broken

[limber adder]

not sure what are the implications for chatgpt-assisted code at least for creating the initial drafts that I'd have to check with my professors ://

[topaz mulch]

are y'all in uni?

[limber adder]

4th year ohio state correct

a butt ton of my assignments have all been in C 👀

[modern pendant]

So can you help my code...

[topaz mulch]

yes

that's good

[topaz mulch]

so did u take from chat gpt?

[limber adder]

depends on definition of "good"; I can't code OOP code for sh1t 😂

[topaz mulch]

but c isn't oop

[limber adder]

exactly that's why I'm weak at OOP which according to my dad is an "industry standard"

[topaz mulch]

oop is an industry standard or being weak at it?

[limber adder]

the former; my father does industry 4.0 work helping to design digital twins and what not

man we really hijacked this thread 😂

[topaz mulch]

nice

lmao

msg to OP:
do you want us to rewrite your code for you?

and you didn't answer my first question

[limber adder]

I downloaded OP's code and gcc'ed it and it's freezing after accepting input for some reason 👀

[topaz mulch]

strange

lemme look at it

[modern pendant]

nah it wasn't gpt

I have the same problem

if I input 4 numbers it sill gives a wrong answer

[topaz mulch]

maybe try using switch statements

[limber adder]

I think the scanf is being "misused" as a preliminary hunch...

[topaz mulch]

yes

i thought the same thing

[modern pendant]

thanks

[limber adder]

also @modern pendant make sure you add an additional percent sign like so:
printf("The numbers must be integers and the operators must be +, -, *, /, or %%!\n")
Helps to get rid of gcc warning 😄

[modern pendant]

oh that was also the problem thank you

[scenic swallow]

I just looked through it and what I found is that you made a mistake when reading the given real language algorithm.

9.
If operator_one is *, /, or %
a) If operator_one is *
(1) Multiply the first_num and the second_num, and store it in firstSecondOutcome
b) Else if operator_one is /
(1) Divide the first_num and the second_num, and store it in firstSecondOutcome
c) Else
(1) Find the remainder of the first_num and the second_num, and store it in firstSecondOutcome
d) Set firstOperatorFlag with value 2
10. Else if operator_two is * /, or %        <-- here you went wrong
a) If operator_two is *      

if (operator_one == '*' || operator_one == '/' || operator_one == '%') {
    if (operator_one == '*') {
        firstSecondOutcome = first_num * second_num;
    } else if (operator_one == '/') {
        firstSecondOutcome = first_num / second_num;
    } else {
        firstSecondOutcome = first_num % second_num;
    }
    firstOperatorFlag = 2;
} else /*  <-- here you should've written 'else if (operator_two == '*' || operator_two == '/' || operator_two == '%' { ... */ {
    ...
}

[limber adder]

nope the scanf was just fine I just checked 😄

but 1+2+3+4 is giving me 7 tho

[modern pendant]

i'll be back within 15 minutes, currently doing it again rn

[limber adder]

Welcome to a working Calculator~!
You will be providing four numbers and four operators
The numbers must be integers and the operators must be +, -, *, /, or %!
Remember that the last operator MUST be an equal sign ~
Please enter the expression below: 
1+2+3+4=
The outcome for the expression came out to be 3
Thank You

huh?

[limber adder]

wait sht sorry wrong patch 🙃

[limber adder]

do you mean?

  // Check for the first operator precedence
  if (operator_one == '*' || operator_one == '/' || operator_one == '%') {
    if (operator_one == '*') {
      firstSecondOutcome = first_num * second_num;
    } else if (operator_one == '/') {
      firstSecondOutcome = first_num / second_num;
    } else {
      firstSecondOutcome = first_num % second_num;
    }
    firstOperatorFlag = 2;
  } else if (operator_two == '*' || operator_two == '/' ||
             operator_two == '%') {
    if (operator_one == '+') {
      firstSecondOutcome = first_num + second_num;
    } else {
      firstSecondOutcome = first_num - second_num;
    }
    firstOperatorFlag = 2;
  }

[crisp pollen]

@modern pendant Has your question been resolved? If so, type !solved :)

[limber adder]

🙃

tedliosu@victus-ted:~/Downloads/programs/from_discord$ ./rando_prog 
Welcome to a working Calculator~!
You will be providing four numbers and four operators
The numbers must be integers and the operators must be +, -, *, /, or %!
Remember that the last operator MUST be an equal sign ~
Please enter the expression below: 
33+22/20+0=
The outcome for the expression came out to be 55
Thank You

man this program is cursed and convoluted fr fr

[crisp pollen]

@modern pendant

Please Do Not Delete Posts!

Please don't delete forum posts. They can be helpful to refer to later and other members can learn from them. In the future you can use !solved to close a post and mark a post as solved.

[modern pendant]

I did it thanks!!

[limber adder]

awesome! 😄

[limber adder]

please use the !solved command to mark this as solved 😄

[modern pendant]

!so;ved

!solved

[crisp pollen]

Thank you and let us know if you have any more questions!

This thread is now set to auto-hide after an hour of inactivity

[topaz mulch]

oh ok it's solved

[limber adder]

neato 😄

[topaz mulch]

if anybody is interested i remade this in c++ with switch statements

[limber adder]

bored? lol

[topaz mulch]

do you want to see it?

[limber adder]

can I download and compile it with g++ without making any changes to it? then sure 😄

[scenic swallow]

Sounds fun, I'll try to craft one together in C++, too

[topaz mulch]

yes

[limber adder]

what advantages do C++ serve here over C btw?

cuz I can't see one tbf

[scenic swallow]

It's just easier to get something running.

Best example is std::vector

Whereas for C you'd have to write your own linked list + insert + remove + whatever you need

[limber adder]

ah yse std::vector is nice indeed 😄

[topaz mulch]

actually i'm using visual studio

[limber adder]

yea screw that lol

[topaz mulch]

so i dunno if it will work with g++

[limber adder]

msvc or "mingw"?

[limber adder]

could you show me the headers here? 👀

[topaz mulch]

#include <iostream>
#include <string>
#include <sstream>

#include <iostream>
#include <string>
#include <sstream>

void mainScreen();
int evaluateExpression(int num1, char op1, int num2, char op2, int num3, char op3, int num4);

int main() {
    mainScreen();
    return 0;
}

void mainScreen() {
    std::cout << "Welcome to the Calculator!" << std::endl;

    std::cout << "Please enter an expression of up to 4 digits (e.g., 5 + 3 * 2 + 3=): ";

    std::string input;
    std::getline(std::cin, input);

    std::istringstream iss(input);
    int num1, num2, num3, num4;
    char op1, op2, op3, equals;

    iss >> num1 >> op1 >> num2 >> op2 >> num3 >> op3 >> num4 >> equals;

    int result = evaluateExpression(num1, op1, num2, op2, num3, op3, num4);
    std::cout << "Result: " << result << std::endl;
}


int evaluateExpression(int num1, char op1, int num2, char op2, int num3, char op3, int num4) {
    int result;
    switch (op2) {
    case '*':
        result = (op1 == '+') ? num1 + num2 * num3 : num1 - num2 * num3;
        break;
    case '/':
        result = (op1 == '+') ? num1 + num2 / num3 : num1 - num2 / num3;
        break;
    case '%':
        result = (op1 == '+') ? num1 + num2 % num3 : num1 - num2 % num3;
        break;
    case '+':
        result = (op1 == '+') ? num1 + num2 + num3 : num1 - num2 - num3;
        break;
    case '-':
        result = (op1 == '+') ? num1 + num2 - num3 : num1 - num2 + num3;
        break;
    }

    switch (op3) {
    case '*':
        result = (op2 == '+') ? result + num4 : result - num4;
        break;
    case '/':
        result = (op2 == '+') ? result + num4 : result - num4;
        break;
    case '%':
        result = (op2 == '+') ? result + num4 : result - num4;
        break;
    case '+':
        result += num4;
        break;
    case '-':
        result -= num4;
        break;
    }
    return result;
}

[limber adder]

ok that might work lemme crack at it real quick

[limber adder]

is this complete? 👀

[topaz mulch]

wry guys i need to go i'll be back in a bit

[topaz mulch]

yes

[scenic swallow]

This doesn't look like it's working properly.
Specifically this part:

case '+':
    result = (op1 == '+') ? num1 + num2 + num3 : num1 - num2 - num3;
    break;
case '-':
    result = (op1 == '+') ? num1 + num2 - num3 : num1 - num2 + num3;
    break;

Also it doesn't seem to look like as if you respected the case for when op1 is also a *, / or %

[limber adder]

is this what you mean?

Welcome to the Calculator!
Please enter an expression of up to 4 digits (e.g., 5 + 3 * 2 + 3=): 4-3+2+1=
Result: 0

[scenic swallow]

No, I meant something like 4 * 3 * 2 * 1

[limber adder]

Damn:

Welcome to the Calculator!
Please enter an expression of up to 4 digits (e.g., 5 + 3 * 2 + 3=): 4*3*2*1=
Result: -3

[scenic swallow]

Even that one wasn't correct

but -3 is wild

[limber adder]

at this point I'd just use a normal calculator 😂

[topaz mulch]

lmao looks like it's not working

[limber adder]

LOL

[topaz mulch]

nvm i give up

🤣

[limber adder]

told ya parsing was hard innit? 😂

[topaz mulch]

ye

wait imma try to fix it actually

[limber adder]

imma try and write some unit tests for this in bash actually 👀

[topaz mulch]

rly?

[limber adder]

or something idk I'm just trying to practice testing as per advice from father 😄

[limber adder]

do you mind if I write tests and you do the actual logic? sorry I'm terrible with parsing stuff lol

and I'm also terrible with C++

[scenic swallow]

My gosh, haha.
I'm in my 4th data structure now.

First I tried with a vector, then a stack, then a queue and now I'm with the deque (I could've just used a vector but I wanted to pick the correct data structure... kill me)

[limber adder]

how's this thus far (without the asserts?)

tedliosu@victus-ted:~/Downloads/programs/from_discord$ ./unit_tests.sh
Testing 1+2+3+4=
Welcome to the Calculator!
Please enter an expression of up to 4 digits (e.g., 5 + 3 * 2 + 3=): Result: 10
Testing 4*3*2*1=
Welcome to the Calculator!
Please enter an expression of up to 4 digits (e.g., 5 + 3 * 2 + 3=): Result: -3
Testing 5*8-9-0=
Welcome to the Calculator!
Please enter an expression of up to 4 digits (e.g., 5 + 3 * 2 + 3=): Result: 6
Testing 4-3+2+1=
Welcome to the Calculator!
Please enter an expression of up to 4 digits (e.g., 5 + 3 * 2 + 3=): Result: 0

[scenic swallow]

First result is correct, all others are wrong

Btw, I'm finished

;compile | 1 + 2 * 4 / 3 - 1 - 1 - 1 - 1 =

#include <iostream>
#include <string>
#include <sstream>
#include <algorithm>
#include <deque>

int eval_expr(std::deque<int> nums, std::deque<char> ops) {
    static int i{};

    while (ops.front() != '=') {
        int n1 = nums.front();
        nums.pop_front();
        char op = ops.front();
        ops.pop_front();
        int n2 = nums.front();
        nums.pop_front();

        switch (op) {
            case '*':
                nums.push_front(n1 * n2);
                break;
            case '/':
                nums.push_front(n1 / n2);
                break;
            case '%':
                nums.push_front(n1 % n2);
                break;
            case '+':
                nums.push_front(n2);
                return n1 + eval_expr(nums, ops);
            case '-':
                nums.push_front(-n2);
                return n1 + eval_expr(nums, ops);
        }
    }

    return nums.front();
}

int main() {
    std::cout << "Welcome to the Calculator!" << std::endl;
    std::cout << "Please enter an expression ending with '='";

    std::string input;
    std::getline(std::cin, input);
    
    /* Code from https://stackoverflow.com/a/83481 . Removes all spaces (wasn't required) */
    /*
    std::string::iterator end_pos = std::remove(input.begin(), input.end(), ' ');
    input.erase(end_pos, input.end());
    */

    std::istringstream iss(input);
    std::deque<int> nums;
    std::deque<char> ops;

    for (;;) {
        int n;
        char c;
        iss >> n >> c;
        nums.push_back(n);
        ops.push_back(c);

        if (c == '=') break;
    }

    std::cout << std::endl << input << " " << eval_expr(nums, ops) << std::endl;
}

[feral delta]

Program Output

Welcome to the Calculator!
Please enter an expression ending with '='
1 + 2 * 4 / 3 - 1 - 1 - 1 - 1 = -1

elmonkeking | 44ms | c++ | x86-64 gcc 13.2 | godbolt.org

[limber adder]

hold on lemme finish building the testing framework 😂

[scenic swallow]

Arbitrary amount of inputs even

Python would be the easiest by far

;compile | 1 + 2 * 4 / 3 - 1 =

equation = input("Please enter an expression ending with '=': ")
print(f"{equation[:-2]} = {eval(equation[:equation.find('=')])}")

[feral delta]

Program Output

Please enter an expression ending with '=': 1 + 2 * 4 / 3 - 1 = 2.6666666666666665

elmonkeking | 62ms | python | Python 3.12 | godbolt.org

[limber adder]

LMAO

[scenic swallow]

could even enforce integer division with a simple replace

;compile | 1 + 2 * 4 / 3 - 1 =

equation = input("Please enter an expression ending with '=': ")
print(f"{equation[:-2]} = {eval(equation.replace('/', '//')[:equation.find('=')])}")

[feral delta]

Program Output

Please enter an expression ending with '=': 1 + 2 * 4 / 3 - 1 = 2

elmonkeking | 87ms | python | Python 3.12 | godbolt.org

[limber adder]

How's this now?

tedliosu@victus-ted:~/Downloads/programs/from_discord$ ./unit_tests.sh
Testing 1+2+3+4=
10 was expected; PASS
Testing 4*3*2*1=
24 was expected, but -3 was actual; FAIL
Testing 5*8-9-0=
31 was expected, but 6 was actual; FAIL
Testing 4-3+2+1=
4 was expected, but 0 was actual; FAIL

[scenic swallow]

How's what?

[limber adder]

the output looking for a testing framework lol?

[topaz mulch]

hey guys

[scenic swallow]

For an actual testing framwork? Bad, because you need to write your own shell script.
For this very case it's okay, however I would probably let it randomly choose operands and operators, evaluate these and then check that the result of your program matches your evaluation

[limber adder]

my "unit_tests.sh" is ready to go for your program; want me to upload the contents lol?

[topaz mulch]

sure why not

[scenic swallow]

And I would make it like a few thousand tests rather than just 4

[limber adder]

sh1t 😂

[limber adder]

#!/bin/bash

# Declare our array of test expressions
test_exps=(
           "1+2+3+4"
           "4*3*2*1"
           "5*8-9-0"
           "4-3+2+1"
          )
name_of_prog="rando_prog_itex"
name_of_exten=".cpp"
result_field_num="19"


# DON'T ALTER ANYTHING BELOW THIS LINE; UNLESS IF YOU KNOW
#    EXACTLY WHAT YOU'RE DOING.

# First argument is expected, second argument is actual :D
assert_expected () {

    if [[ "$1" -eq "$2" ]]; then
        echo "$2 was expected; PASS"
    else
        echo "$1 was expected, but $2 was actual; FAIL"
    fi

}

g++ "${name_of_prog}${name_of_exten}" -o "$name_of_prog"

for expressn in "${test_exps[@]}"; do
    echo "Testing $expressn="
    actual_ans=$(echo "${expressn}=" | "./$name_of_prog" | cut -d" " -f"$result_field_num" | tr -d "\n")
    expected_ans="$(echo "${expressn}" | bc)"
    assert_expected "$expected_ans" "$actual_ans"
done

# Cleanup
rm -rf "$name_of_prog"

[topaz mulch]

i don't know anything about bash really, but i guess this will test my program

[limber adder]

unfortunately I made it so that you have to edit the contents of "test_exps" in order to have additional test expressions, and this shell script can only run with bash 🙃

[limber adder]

you're on windows right? so that means that this will somehow have to be converted to powershell i think ://

[topaz mulch]

yep on windows

nvm my program was broken anyway

i have a new version now

[limber adder]

I can test that new version if you'd like 😄

[topaz mulch]

it even throws an error when there is a modulo or adivision by zero

[limber adder]

ok sounds good tysm for chipping in 🙏

[topaz mulch]

wait

i found an error

i need to take into account PEMDAS

should i make it so it uses parenthesis?

[limber adder]

no that'll be too complicated :/

[topaz mulch]

ok

so here is my final version

ignore the" c++"

ok imma stop here

[limber adder]

LGTM:

tedliosu@victus-ted:~/Downloads/programs/from_discord$ ./unit_tests.sh 
Testing 1+2+3+4=
10 was expected; PASS
Testing 4*3*2*1=
24 was expected; PASS
Testing 5*8-9-0=
31 was expected; PASS
Testing 4-3+2+1=
4 was expected; PASS
Testing 3*4/9+9=
10 was expected; PASS
Testing 4*7+2+64=
94 was expected; PASS
Testing 34*6*1+3=
207 was expected; PASS
Testing 2-5+43-4=
36 was expected; PASS
Testing 3-54*43*43=
-99843 was expected; PASS
Testing 4-2*65/4=
-28 was expected; PASS
Testing 54-3-47-2=
2 was expected; PASS

[topaz mulch]

cool

try it with more

[limber adder]

Tired of writing code for now imma take a break lol