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C++ segmentation fault while checking for null pointer

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# 1  
Old 02-19-2010
C++ segmentation fault while checking for null pointer
Code:
void disptree(node *ptr)
{
    if ((ptr->left) !=NULL)
    disptree(ptr->left);

    cout<<"Position:"<<ptr->pos<<" Data:"<<ptr->data<<endl;

    if ((ptr->right)!=NULL;
    disptree(ptr->right);
}

i'm getting a segmentation fault at the red line. i cannot understand what's the problem. Help me out.
Thanks in advance..
Last edited by vino; 02-19-2010 at 02:47 AM.. Reason: added code tags
# 2  
Old 02-19-2010
You may also want to check if ptr is null or not. Something like

Code:
if (ptr && (ptr->left) !=NULL)

And likewise with ptr->right.
# 3  
Old 02-19-2010
Hi Vijay,

You are passing a pointer to this function. Ensure that the pointer is valid from where you called this fuction. It should not be pointing to deleted are freed objects.

-Vijay
# 4  
Old 02-21-2010
Thank you ppl
Thank u for ur time ppl. made a mistake at other part of prog so null was being to ptr...
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