I am getting Access violation after running this code. Can anyone help?

Question

0.00/5 (No votes)

See more:

C++

int GetLength(const char* string)
{
  int iLength;
  for(iLength = 0; (*(string + iLength) != '\0'); iLength++)
    ;
  return iLength;
}
void Reverse(char* string)
{
  int iLength = GetLength(string);
  char* pTemp = new char[iLength+1];
  memcpy(pTemp, string, iLength+1);
  for(int i = 0; i < iLength; i++)
  {
    *(string+i) = *(pTemp + iLength - i -1);//Access violation in first iteration
  }
  *(pTemp+iLength) = '\0';
  delete []pTemp;
  pTemp == NULL;
}

Posted 3-Dec-14 17:51pm

Shubha Debnath

Add a Solution

Comments

Mohibur Rashid 4-Dec-14 0:41am

You have sent constant string as data to Reverse function, I suppose. You can't do that. It will definitely generate error. Besides your logic is not good enough to reverse an string.

Shubha Debnath 4-Dec-14 1:13am

Yes I understand and the problem get resolved. Previously I was sending a constant sting; that is why it does not allow me to assign value. Now I have allocated the string before calling the function and it worked.

Thanks Mohibur. Please give me a better idea of reversing a string.

3 solutions

Solution 2

The code you posted works, provided the string you pass to Reverse() is really a 0-terminated string! You should at the very least test string against nullptr, because that's pretty much the only thing that could cause an access violation:

C++

void Reverse (char* string) {
   if (string == nullptr)
      return;
   ...
}

If that's not it (or even if it is!), learn to use a debugger, break at the point where you get the access violation, and check the current values of your variables.

Posted 3-Dec-14 21:05pm

Stefan_Lang

Solution 3

As a matter of fact, I should not offer you any solution. But here is the thing you can do, very simple:

C++

for(i=0;i<len;i++) 
{
 swap(str+i, str-i);// you should write the swap function or related code and also figure out how it works 
}

And also try to understand what stephan lang have said

Posted 3-Dec-14 21:26pm

Mohibur Rashid

v2

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)

Sinisa Hajnal · Accepted Answer · 2014-12-03T20:39:00

C++

string t = string ( t.rbegin(), t.rend() );

string ( ) is the string constructor which creates a new string object ( String definition[^] )

rbegin and rend are reverse iterators, an iterator is an object which acts in a similar way to a pointer ( Reverse iterator link[^]
rbegin link[^] )

string ( tekst.rbegin(), tekst.rend() ) creates a string from the beginning to the of the reversed 't'

If this helps please take time to accept the solution. Thank you.