C# C# easy homework, math not working. int equal = numbers.max()-numbers.min() <- ??

[C#] C# easy homework, math not working. int equal = numbers.max()-numbers.min() <- ?? - Printable Version

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+---- Thread: [C#] C# easy homework, math not working. int equal = numbers.max()-numbers.min() <- ?? (/showthread.php?tid=2175883)

C# easy homework, math not working. int equal = numbers.max()-numbers.min() <- ?? - svavart - Feb 3, 2012

The following code won't show the correct answer.
(Suppose to show the answer to highest number - lowest number.)
code:

Code 
string texti = textBox1.Text;

                    string[] strengur = texti.Split(',');

                    int[] tolur = new int[texti.Length];

                    int mismunur = 0 ;

                    //var hætta

                    for (int i = 0; i < strengur.Length; i++)

                    {

                        tolur[i] = Convert.ToInt32(strengur[i]);

                    }

                    //test

                    MessageBox.Show(tolur.Max()+","+tolur.Min());

                    //test

                    mismunur = tolur.Max()-tolur.Min();

                    MessageBox.Show("Lesnar voru inn tölurnar:\n"+texti+"\n En mismunurinn á hæstu og lægstu tölunni er:"+mismunur);

* - Silicon - Feb 3, 2012

Change this line:

Code 
int[] tolur = new int[texti.Length];

Code 
int[] tolur = new int[tolur.Length];

* - svavart - Feb 3, 2012

(Feb 3, 2012 01:24 PM)AntiHelix Wrote: Change this line:

Code
int[] tolur = new int[texti.Length];
to

Code
int[] tolur = new int[tolur.Length];

Just got an error "the use of an unassigned variable"
By the way that line I use to be sure the array has enough "compartments" for the numbers in the textbox1 which are separated by a ",".

Everything works, even the .max number and the .min numbers are correct it's just that the subtraction doesn't seem to work. =/

//full code with irrelevant stuff

Code 
using System;

using System.Collections.Generic;

using System.ComponentModel;

using System.Data;

using System.Drawing;

using System.Linq;

using System.Text;

using System.Windows.Forms;

namespace Verk_3

{

    public partial class Form1 : Form

    {

  public Form1()

  {

    InitializeComponent();

  }

  private void Form1_KeyDown(object sender, KeyEventArgs e)

  {

    if (e.KeyCode == Keys.Enter)

    {

    if (textBox1.Text != null)

    {

    string texti = textBox1.Text;

    string[] strengur = texti.Split(',');

    int[] tolur = new int[texti.Length];

    int mismunur = 0 ;

    //var hætta

    for (int i = 0; i < strengur.Length; i++)

    {

    tolur[i] = Convert.ToInt32(strengur[i]);

    }

    //test

    MessageBox.Show(tolur.Max()+","+tolur.Min());

    //test

    mismunur = tolur.Max()-tolur.Min();

    MessageBox.Show("Lesnar voru inn tölurnar:\n"+texti+"\n En mismunurinn á hæstu og lægstu tölunni er:"+mismunur);

    }

    }

  }

    }

}

* - Gh0st-Zer0 - Feb 3, 2012

This is the working code for UInt64 numbers which mean that you can insert From 0 to 18,446,744,073,709,551,615 which equals 2^64 − 1 numbers.

I have also commented the code so to be understandable.

This is Consoled based algorythm just change it and modify it into your app!

Code 
//First of all we need UInt64 to calculate really long numbers.

string Input = "18446744073709551615,100";

/*We split the numbers in the text by ',' (comma) 

and put them in an array named Numbers*/

string[] Numbers = Input.Split(',');

//This will help us to convert the string into number.

UInt64[] ConvertedNum = new UInt64[Numbers.Length];

/*We convert the string into an integer and put it 

in the tolur array.*/

for (int i = 0; i < Numbers.Length; i++)

{

  ConvertedNum[i] = Convert.ToUInt64(Numbers[i]);

}

//We Find the Difference between the max and the min Number.

UInt64 Difference = ConvertedNum.Max() - ConvertedNum.Min();

Console.WriteLine("Were read into the numbers:\n" + Input + 

"\nBut the difference between the highest and lowest number is:\n" + Difference);

Console.ReadKey();

Execution Result:

Code 
Were read into the numbers:

18446744073709551615,100

But the difference between the highest and lowest number is:

18446744073609551615

* - E25EB8582FF05BF - Feb 3, 2012

@Ghost. Should we read your sound and well in code commented answer as a sign you're irritated by the lack of self involvement of those lazy "students" expecting us to do their homework ?

* - svavart - Feb 3, 2012

(Feb 3, 2012 05:12 PM)Gh0st-Zer0 Wrote: This is the working code for UInt64 numbers which mean that you can insert From 0 to 18,446,744,073,709,551,615 which equals 2^64 − 1 numbers.

I have also commented the code so to be understandable.

This is Consoled based algorythm just change it and modify it into your app!

Code
//First of all we need UInt64 to calculate really long numbers. string Input = "18446744073709551615,100"; /*We split the numbers in the text by ',' (comma) and put them in an array named Numbers*/ string[] Numbers = Input.Split(','); //This will help us to convert the string into number. UInt64[] ConvertedNum = new UInt64[Numbers.Length]; /*We convert the string into an integer and put it in the tolur array.*/ for (int i = 0; i < Numbers.Length; i++) { ConvertedNum[i] = Convert.ToUInt64(Numbers[i]); } //We Find the Difference between the max and the min Number. UInt64 Difference = ConvertedNum.Max() - ConvertedNum.Min(); Console.WriteLine("Were read into the numbers:\n" + Input + "\nBut the difference between the highest and lowest number is:\n" + Difference); Console.ReadKey();

Execution Result:

Code
Were read into the numbers: 18446744073709551615,100 But the difference between the highest and lowest number is: 18446744073609551615

The teacher didn't go in dept about what the usual "int" was capable to do so thanks ;), also thanks for taking time to comment the code. Too many that decide not to.

tolur = numbers
texti = text
strengur = string
Forgot to include.

* - Gh0st-Zer0 - Feb 3, 2012

(Feb 3, 2012 06:46 PM)E25EB8582FF05BF Wrote: @Ghost. Should we read your sound and well in code commented answer as a sign you're irritated by the lack of self involvement of those lazy "students" expecting us to do their homework ?

Well he did the half job so i just help a little to complete! Of course i'm not the guy that support lazy Students! I'm a Univercity student and i hate guys that C/P other work and present them us theirs!

* - Silicon - Feb 4, 2012

Sorry for my last post, I was tired and I changed it to the wrong variable.
Change this line:

Code 
int[] tolur = new int[texti.Length];

to:

Code 
int[] tolur = new int[strengur.Length];

If you set it to texti.Length, you are setting the array size to the amount of characters in the text box. What if you had a 10-digit-long number, but only that number? Then you'd have 10 spaces in the array, but only working with 1 number. Because strengur is the text split up via ,, you are setting it to the number of items separated by ,s in the text.

* - svavart - Feb 4, 2012

(Feb 3, 2012 06:59 PM)Gh0st-Zer0 Wrote: Well he did the half job so i just help a little to complete! Of course i'm not the guy that support lazy Students! I'm a Univercity student and i hate guys that C/P other work and present them us theirs!

I'm at the early stage of learning the programming basics with c# and there are already plenty of students to lazy to do their own work. Unfortunately for them there is a program that cross-checks all the students projects when you've made it to advanced programming.

(Feb 4, 2012 03:43 AM)AntiHelix Wrote: If you set it to texti.Length, you are setting the array size to the amount of characters in the text box. What if you had a 10-digit-long number, but only that number? Then you'd have 10 spaces in the array, but only working with 1 number. Because strengur is the text split up via ,, you are setting it to the number of items separated by ,s in the text.

Thanks, I understand what you mean now, feel a bit stupid for not noticing that. ;)

* - Gh0st-Zer0 - Feb 4, 2012

(Feb 4, 2012 04:56 AM)svavart Wrote: I'm at the early stage of learning the programming basics with c# and there are already plenty of students to lazy to do their own work. Unfortunately for them there is a program that cross-checks all the students projects when you've made it to advanced programming.

Well if it's like that. . .
Good Then! 🙂