C#

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✅ (Very Begginer) - I Get errors when I can't access method within other class and syntax

SStr1ke1/19/2023

I have a class " Course " and a class "University", in class Course there is a Code for each teacher (Between 1 and 15)
I need to find the MostCommon teacher that has the most Courses in the University.
$code

MMODiX1/19/2023

To post C# code type the following:
```cs
// code here
```

Get an example by typing $codegif in chat

If your code is too long, post it to: https://paste.mod.gg/

SStr1ke1/19/2023

        public int Mostcommon()
        {
            int[] arr = new int[15];
            for(int i = 0; i < PlaceCourse.Length; i++)
            {
                arr[PlaceCourse.GetCode()]++;
            }
            int MostCommon;
            for (int x = 0; x < arr.Length - 1; x++)
                MostCommon = Math.Max(arr[x], arr[x + 1]);
            for(int y = 0; y < arr.Length; y++)
                if (MostCommon == arr[y])
                {
                    return y;
                }
        }

SStr1ke1/19/2023

    internal class Course
    {
        private string CourseName;
        private int WeekHours;
        private int Code;
        public int GetCode()
        {
            return Code;
        }
    }

SStr1ke1/19/2023

The access other class error is fixed

SStr1ke1/19/2023

But there is syntax error with MostCommon

SStr1ke1/19/2023

(int MostCommon)

SStr1ke1/19/2023

And if you know a more efficient/better way of doing this I will be very glad to hear it

SStr1ke1/19/2023

Because I'am pretty positive mine is not so good

SStr1ke1/19/2023

        public int Mostcommon()
        {
            int[] arr = new int[15];
            for(int i = 0; i < PlaceCourse.Length; i++)
            {
                arr[PlaceCourse[i].GetCode()]++;
            }
            int MostCommon;
            for (int x = 0; x < arr.Length - 1; x++)
                MostCommon = Math.Max(arr[x], arr[x + 1]);
            int y;
            for (int y = 0; y < arr.Length; y++)
                if (MostCommon == arr[y])
                {
                    y = arr[y];
                }
            return y;
        }

SStr1ke1/19/2023

I had to put "return y" out side the loop because it said that "not all code paths return"

SStr1ke1/19/2023

And now I get syntax error with y as well

MMODiX1/19/2023

you probably want $scopes

Hhiyosilver1/19/2023

$scopes

MMODiX1/19/2023

scope A {
  thing a;
  scope B {
    thing b;
  }
}

thing a is available in scope A and scope B
thing b is available only in scope B

Hhiyosilver1/19/2023

You are trying to return y which was defined inside your for loop.

Hhiyosilver1/19/2023

I assume that causes your syntax error.

SStr1ke1/19/2023

But isn't it if it's inside the scopes of the whole method

SStr1ke1/19/2023

it should be defined inside all of it?

Hhiyosilver1/19/2023

You could define y at the very top so it's in scope for all of it.

SStr1ke1/19/2023

It didn't change much xd

SStr1ke1/19/2023

I guess the problem is that it's value is defined inside the loop

SStr1ke1/19/2023

but I don't know how can I define it without getting the error

SStr1ke1/19/2023

because I need the loop to define it

Hhiyosilver1/19/2023

Give me a second, had to switch from phone to pc

SStr1ke1/19/2023

Yeah I noticed that xd

SStr1ke1/19/2023

Thank you

Hhiyosilver1/19/2023

No idea how people get stuff done on their phones. Just awful all around.

Hhiyosilver1/19/2023

Anyway, so I see now what this is supposed to do

Hhiyosilver1/19/2023

If we start at the top, you know how many courses there are from PlaceCourse no?

SStr1ke1/19/2023

Only if you could see my screen...xd

SStr1ke1/19/2023

YOu mean like what is the size of PlaceCourse?

SStr1ke1/19/2023

If so, yeah that's a 1000

SStr1ke1/19/2023

private Course[] PlaceCourse;
private int current=0;
public University()
{
PlaceCourse = new Course[1000];
}

SStr1ke1/19/2023

done it in a constructor

SStr1ke1/19/2023

previoulsy

Hhiyosilver1/19/2023

Oh wait, I'm dumb yeah that makes more sense

Hhiyosilver1/19/2023

Array contains up to 15 ids for each of the teachers

Hhiyosilver1/19/2023

Are you sure they go from 1 to 15?

SStr1ke1/19/2023

yes

SStr1ke1/19/2023

that is declared in the question

Hhiyosilver1/19/2023

because you are accessing the array with indices 1 to 15 then, but it only goes from 0 to 14

Hhiyosilver1/19/2023

int[] arr = new int[15];
            for(int i = 0; i < PlaceCourse.Length; i++)
            {
                arr[PlaceCourse.GetCode()]++;
            }

Hhiyosilver1/19/2023

if GetCode ever returned 15 for any teacher, this would explode

SStr1ke1/19/2023

Oh yeah, Ig it's better to write it as 16

SStr1ke1/19/2023

and start from 1

Hhiyosilver1/19/2023

you could just use

Hhiyosilver1/19/2023

GetCode() - 1 to index into the array.

Hhiyosilver1/19/2023

You should probably leave it starting at 0, that's pretty standard.

SStr1ke1/19/2023

But then it will return the index with the code-1

SStr1ke1/19/2023

And that won't be the right teacher

Hhiyosilver1/19/2023

It will be if you always access it like that

Hhiyosilver1/19/2023

Lets say you ask "How many courses does the teacher with Id 8 have"?

Hhiyosilver1/19/2023

its arr[8 - 1]

Hhiyosilver1/19/2023

i.e. the 8th index of your array.

Hhiyosilver1/19/2023

Which by convention starts at index 0, not 1 🙂

SStr1ke1/19/2023

True, but the question wants me to return a number between 1 and 15

Hhiyosilver1/19/2023

I supposed you could just increase it to 16 and just leave the 0 slot empty, but I would suggest that that's not good practice and is more likely to confuse you later.

Hhiyosilver1/19/2023

You can still do that

Hhiyosilver1/19/2023

So you want the most common teacher Id from all the courses.

SStr1ke1/19/2023

yeah

Hhiyosilver1/19/2023

You already define int MostCommon so thats almost certainly going to be what you want to return

Hhiyosilver1/19/2023

rather than 1

Hhiyosilver1/19/2023

Now lets see how you set it

SStr1ke1/19/2023

The ' y ' is the Index (ID of the teacher)

Hhiyosilver1/19/2023

I see you are looping once to find the actual number of courses

Hhiyosilver1/19/2023

And then again to find the index of that count

Hhiyosilver1/19/2023

You could probably just do that in one go

SStr1ke1/19/2023

Once to find the teached with the most courses and then to find his index

SStr1ke1/19/2023

yeah

Hhiyosilver1/19/2023

something like

int mostCommon;
int maxCount = 0;
for(int i = 0; i < arr.Length; i++) {
  if(arr[i] > maxCount) {
    maxCount = arr[i];
    mostCommon = i + 1;
  }
}
return mostCommon;

Hhiyosilver1/19/2023

Deal with the teacher id like its 0 based for indexing purposes, then only add back one to make it human-readable at the end.

Hhiyosilver1/19/2023

Something like this, I don't know.

Hhiyosilver1/19/2023

There is probably something nicer you can do, but this should work.

SStr1ke1/19/2023

wait

SStr1ke1/19/2023

Let me process that real quick xd

Hhiyosilver1/19/2023

actually, let me make a quick edit, that was dumb by me

Hhiyosilver1/19/2023

This is better, so you can just cleanly return mostCommon

Hhiyosilver1/19/2023

Technically this doesn't cover a case where no teacher has any courses, not sure what you'd want to happen there.

SStr1ke1/19/2023

the question says that there is one for sure

SStr1ke1/19/2023

$code

MMODiX1/19/2023

To post C# code type the following:
```cs
// code here
```

Get an example by typing $codegif in chat

If your code is too long, post it to: https://paste.mod.gg/

SStr1ke1/19/2023

        public int Mostcommon()
        {
            int[] arr = new int[15];
            for(int i = 0; i < PlaceCourse.Length; i++)
            {
                arr[PlaceCourse[i].GetCode()]++;
            }
            int MostCommon = arr[0];
            int Index = 0;
            for (int x = 1; x < arr.Length - 1; x++)
            {
                if (MostCommon < arr[x])
                {
                    MostCommon = arr[x];
                    Index = x;
                }
            }
            return Index+1;
        }

SStr1ke1/19/2023

Won't it just returd 0+1 every time now?

SStr1ke1/19/2023

return*

Hhiyosilver1/19/2023

Only if Index never gets set.

Hhiyosilver1/19/2023

That would be the case, if arr[0] is already the most common id

Hhiyosilver1/19/2023

also, you are skipping 1 at the end

Hhiyosilver1/19/2023

in your for loop condition

SStr1ke1/19/2023

oy vey

SStr1ke1/19/2023

forgor to delete it from previous

Hhiyosilver1/19/2023

You dont need to do that anymore, since oyu arent comparing neighbouring indices .)

Hhiyosilver1/19/2023

Yeah

SStr1ke1/19/2023

so even tho it's value is redeclared inside a loop

SStr1ke1/19/2023

It will see that?

Hhiyosilver1/19/2023

You aren't redefining it in this case.

Hhiyosilver1/19/2023

Index refers to a variable outside the loop

Hhiyosilver1/19/2023

you are just assigning to it

Hhiyosilver1/19/2023

But that doesn't need to happen, if that assignment never gets hit, Index just retains the value you defined at first