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Aug 27th, 2004

Re: Need help figuring out C++ Pointers

ok i ran this code now and i get s s not x x...are you sure x x is right????
char var1='s';
char var2='x';
char *ptr1, *ptr2;
ptr1=&var1;
ptr2=&var2;
*ptr2=*ptr1;
cout << *ptr1 << " " << var2 << endl;

hfick

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Aug 27th, 2004

Re: Need help figuring out C++ Pointers

:o sorry, just now i refer to the first code that you given. The right answer is s s.

hail2dthief

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Aug 27th, 2004

Re: Need help figuring out C++ Pointers

&val means address of the varialble var
*p (if is a pointer (int *p

) means value at address pointed at by p.Changes this will change the variable it points to.

int val = 1;
p=&val;
val+=10

cout<<val<<" *p="<<*p; //output is the same for both
(*p) += 4; //changes the value of val
cout<<val<<" *p="<<*p; //output is the same for both

The outputs are:
11 11
15 15

FireNet

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Aug 27th, 2004

Re: Need help figuring out C++ Pointers

Quote originally posted by hfick ...

the next question asks says i am supposed to state the data type of each variable...
double var1, *ptr1, *ptr2;
float *ptr3;
int var2, *var4

so what would the data type of ptr1 be? would it be just ptr1 since it doesn't have the (*) in front of it or how does that work?

hfick

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Aug 27th, 2004

Re: Need help figuring out C++ Pointers

Here's a link:Check it and see, ask if in doubt

http://www.daniweb.com/techtalkforums/thread9878.html

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Aug 27th, 2004

Re: Need help figuring out C++ Pointers

Quote originally posted by hfick ...

so what would the data type of ptr1 be? would it be just ptr1 since it doesn't have the (*) in front of it or how does that work?

Uh, look up a couple posts where I answered that.

Dave Sinkula

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Oct 27th, 2004

Re: Need help figuring out C++ Pointers

Quote originally posted by hfick ...

I am supposed to figure out what the output produced would be from this equation..can anyone help me and explain it to me

char var1='s';
char var2='x';
char *ptr1, *ptr2;
ptr1=&var2;
*ptr2=*ptr1;
cout << *ptr1 << " " < var2 << endl;

-----------------------------------------------------------
output will be
X X
because ptr1 point to the var2 and var2 contain value 'x';

manoj9_5

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Oct 27th, 2004

Re: Need help figuring out C++ Pointers

Quote originally posted by manoj9_5 ...

-----------------------------------------------------------
output will be
X X
because ptr1 point to the var2 and var2 contain value 'x';

Not necessarily. At that point dereferencing an uninitialized pointer has caused undefined behavior. After that, nothing is guaranteed to work, even if it would otherwise.

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