 |  |  |  |  |  |  |  |
New to C++ Pointers and need help with identifying where the errors are
Please support our C++ advertiser: Programming Forums - DaniWeb Sister Site
 |
I am stuck on this problem..you are supposed to locate the error in the segment of code:
char var1, ptr1;
var1='X';
ptr1=&var1;
Can someone please help me figure this out. It is much appreciated.
char var1, ptr1;
var1='X';
ptr1=&var1;
Can someone please help me figure this out. It is much appreciated.
[QUOTE=hfick]I am stuck on this problem..you are supposed to locate the error in the segment of code:
char var1, ptr1;
var1='X';
ptr1=&var1;
Can someone please help me figure this out. It is much appreciated.
I think their needs to be an * by the ptr1 where the variable is declared but I am really not sure.??
char var1, ptr1;
var1='X';
ptr1=&var1;
Can someone please help me figure this out. It is much appreciated.
I think their needs to be an * by the ptr1 where the variable is declared but I am really not sure.??
C++ Syntax (Toggle Plain Text)
It's important to remember that you need '*' for each pointer variable. Therefore: char* ptr1, ptr2; doesn't work as intended.
For two ptrs, you must do char *ptr1, *ptr2.
Ed
[QUOTE=hfick]
•
•
•
•
Originally Posted by hfick
I am stuck on this problem..you are supposed to locate the error in the segment of code:
char var1, ptr1;
var1='X';
ptr1=&var1;
Can someone please help me figure this out. It is much appreciated.
I think their needs to be an * by the ptr1 where the variable is declared but I am really not sure.??
•
•
•
•
In a world without walls or fences,
What use are Windows and Gates.
That is what I thought for the one above...But I am stuck again on this one..could you possibly help again?
char c='A';
char *p;
p=c
* goes here right?? char *c='A';
char *p;
p=c;
hopefully i am getting this..please let me know if this is right
char c='A';
char *p;
p=c
* goes here right?? char *c='A';
char *p;
p=c;
hopefully i am getting this..please let me know if this is right
C++ Syntax (Toggle Plain Text)
•
•
•
•
In a world without walls or fences,
What use are Windows and Gates.
thank you..you must really get this stuff..must be nice...could you help me some more...
var1's address is 55441
int var1=2323;
int *ptr;
ptr=&var1;
var1=?
ptr=?
*ptr=?
var1's address is 55441
int var1=2323;
int *ptr;
ptr=&var1;
var1=?
ptr=?
*ptr=?
Thank you shalin....THat is what I thought but wasn't for sure...
THis one wants to know what the output produced is when the code is executed:
char var1 = 's';
char var2 = 'x';
char *ptr1, *ptr2;
ptr1=&var1;
ptr2=&var2;
*ptr2=*ptr1;
cout << *ptr1 << " " << var2 << endl;
THis one wants to know what the output produced is when the code is executed:
char var1 = 's';
char var2 = 'x';
char *ptr1, *ptr2;
ptr1=&var1;
ptr2=&var2;
*ptr2=*ptr1;
cout << *ptr1 << " " << var2 << endl;
•
•
Join Date: May 2004
Posts: 256
Reputation: 
Solved Threads: 6
Posting Whiz in Training
Try to understand the concept of pointers rather.It's simple actually.A pointer points to the address in memory of a variable.That way if you change one, the changes can be seen at all places.Multiple pointer can point to a variable.
A var can be tought of as a TV and the pointer a Remote Control.Change the channel anywhere,the result is on the TV.And a TV can have multiple remotes
Look below:
&val means address of the variable 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
*(p++) increses the address to which it points to by the pointers datatype size.
*(p)++ increses the val at the address pointed by p by 1.
Understand the pointer concept ?
A var can be tought of as a TV and the pointer a Remote Control.Change the channel anywhere,the result is on the TV.And a TV can have multiple remotes
Look below:
&val means address of the variable 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
*(p++) increses the address to which it points to by the pointers datatype size.
*(p)++ increses the val at the address pointed by p by 1.
Understand the pointer concept
? |
Other Threads in the C++ Forum
- Previous Thread: *Pointer program problem.
- Next Thread: Major problem with C++ compiler
Views: 2939 | Replies: 9
| Thread Tools | Search this Thread |
Latest C++ Posts
- Today's Posts
- Unanswered Threads
Related Forum Features
Tag cloud for C++
6 api application array arrays based beginner binary bmp c++ c/c++ calculator char char* class classes code compile compiler console conversion convert count data delete deploy dll download dynamiccharacterarray encryption error file format forms fstream function functions game givemetehcodez graph homeworkhelp iamthwee ifstream input int java lib library lines list loop looping loops map math matrix memory newbie news number numbertoword output pointer problem program programming project python random read recursion recursive reference return rpg search simple sort sorting spoonfeeding string strings struct temperature template templates text tree url variable vector video visual visualstudio void win32 windows winsock wordfrequency wxwidgets
