help!!! string convert

Question

1.00/5 (2 votes)

See more:

hiii,
how can i do my project?

C#

string str1="4567995244...4457";
string str2="1458795568...85498";

str1+str2; // addition
str1-str2; // differance
str1*str2; // multiplication
str1/str2; // division

note: we dont use biginteger class also
we dont use arithmetic operatiors

Posted 29-Dec-12 5:38am

Orhss

Updated 29-Dec-12 5:44am

Wendelius

v2

Add a Solution

Comments

Sergey Alexandrovich Kryukov 29-Dec-12 21:53pm

What's wrong with BigInteger?
—SA

3 solutions

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

Wendelius · Answer 1 · 2012-12-29T05:52:00

Solution 2

If I understood your question correctly, you first have to change the data type to something you can use in calculation. For example:

C#

int a = int.Parse("123") + int.Parse("456");

Of course you would use variables inside TryParse instead of constant strings.

Posted 29-Dec-12 5:52am

Wendelius

Comments

Sergey Alexandrovich Kryukov 29-Dec-12 21:50pm

Parse is better, because this API name correctly tell us what really happens, unlike "Convert". My 5.
—SA

Wendelius 4-Jan-13 15:07pm

That's true, thanks :)

**Zoltán Zörgő** · Answer 2 · 2012-12-29T07:01:00

Solution 3

If BigInteger is not good enough, look around here: http://www.codeplex.com/Wikipage?ProjectName=sine[^]

Posted 29-Dec-12 7:01am

Zoltán Zörgő

Comments

Sergey Alexandrovich Kryukov 29-Dec-12 21:53pm

Interesting, my 5. However, OP's idea about not using BigInteger is not motivated; most likely, this is just a mistake. As a rule of thumb, OP's "I want" or "I don't want" cannot be taken seriously.
—SA

Zoltán Zörgő 30-Dec-12 2:55am

Probably. But most likely the OP was told to implement these basic operation as pure symbol/string manipulation.

Sergey Alexandrovich Kryukov 30-Dec-12 13:16pm

Agree...
—SA

Thomas Daniels · Answer 3 · 2012-12-29T05:48:00

Solution 1

Hi,

Try this:

C#

string str1="4567995244...4457";
string str2="1458795568...85498";

decimal d1 = Convert.ToDecimal(str1);
decimal d2 = Convert.ToDecimal(str2);

decimal addition = d1+d2; // addition
decimal difference = d1-d2; // difference
decimal multiplication = d1*d2; // multiplication
decimal division = d1/d2; // division

[EDIT]

I've read your comment. So, this is my edit.

Orhss wrote:
note: we dont use biginteger class also

I think there's no other option then using a BigInteger. Add a reference to System.Numerics.dll, add

C#

using System.Numerics;

to the top of your code file, and then use this code:

C#

BigInteger b1 = BigInteger.Parse(str1);
BigInteger b2 = BigInteger.Parse(str2);

BigInteger addition = b1 + b2;
BigInteger difference = b1 - b2;
BigInteger multiplication = b1 * b2;
BigInteger division = b1 / b2;

Hope this helps.

Posted 29-Dec-12 5:48am

Thomas Daniels

Updated 29-Dec-12 6:49am

v2

Comments

ridoy 29-Dec-12 12:20pm

+5

Thomas Daniels 29-Dec-12 12:21pm

Thank you!

Orhss 29-Dec-12 12:33pm

your solution is true but we should use very long string
ex:
12345678901234567891234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890
like this...
thanks

Thomas Daniels 29-Dec-12 12:49pm

I updated my answer.

Orhss 29-Dec-12 13:25pm

right,but we should not use biginteger class and arithmetic operations

Thomas Daniels 29-Dec-12 13:28pm

Why not?

Orhss 29-Dec-12 13:37pm

our project

Thomas Daniels 29-Dec-12 13:38pm

I don't understand.

Orhss 29-Dec-12 13:38pm

i think so we do with multi arrays

Thomas Daniels 29-Dec-12 13:39pm

So?
Why should you not use BigInteger in your project?

Sergey Alexandrovich Kryukov 29-Dec-12 21:54pm

Gibberish. Unless you clearly explain why not BigInteger, no one will take is seriously.
—SA

Orhss 29-Dec-12 13:41pm

using System;

class Program
{
static void Main()
{
string number1 = "12345678978945612378945612378945612378945664563214722155278954";
string number2 = "7894561233214569877896541233214569874563258966558632889625";
string number3 = Add(number1, number2);
Console.WriteLine(number3);
Console.ReadKey();
}

static string Add(string n1, string n2)
{
int len1 = n1.Length;
int len2 = n2.Length;
int max = Math.Max(len1, len2);
int[] ia1 = new int[max];
int[] ia2 = new int[max];
int[] ia3 = new int[max + 1]; // allow for carry forward
for(int i = max - len1; i < max; i++) ia1[i] = n1[i + len1 - max] - 48;
for(int i = max - len2; i < max; i++) ia2[i] = n2[i + len2 - max] - 48;
int sum = 0;
int carry = 0;

for(int i = max - 1; i >= 0; i--)
{
sum = ia1[i] + ia2[i] + carry;
ia3[i + 1] = sum % 10;
carry = sum / 10;
}

if (carry == 1) ia3[0] = 1;
char[] c3 = new char[max + 1];
for(int i = 0; i < max + 1; i++) c3[i] = (char)(ia3[i] + 48);
return new string(c3).TrimStart('0');
}
}

Orhss 29-Dec-12 13:42pm

like this
but we dont use arithmetic operators

Orhss 29-Dec-12 13:48pm

im a student our lecturer wants to without biginteger class

Thomas Daniels 29-Dec-12 14:22pm

I understand. In that case, have a look at Solution 3.