I am struggling with the pointer to 2D-array (cf: 2D array of pointers). Can anybody help me elaborate how the pointerxmoves in the memory to access the individual of y[2][6], especially the high lighted lines?
I have talked to one of the curators of the forum, but I am still not quite clear.
Here is my code:
1) Although y and &y are the same, but x = y issues warning;
2) Q1a/Q2a is the part I think I understand which is the first element of each row of y.
3) but Q1b/c, and Q2b/c turns out to be 3-D to me.
Can anybody give me a diagram how pointer x moves in the memory for each member of y?
4) Line 9: int (*a[8])[5]; is related, and I put it here for future reference but skip it at this moment.
void main()
{
int a={1,2,3,4,5,6,7,8,9,10};
int *p=a;
int *q=&a;
cout<<q-p+1<<endl;
}
The output is 10, how?
if we give cout<<q it will print the address, value won't print....
if we give cout<<p it will print the address, value won't print....
p has the base addr; q... (1 Reply)
All ..
I am having a pointer array . And trying to store the addess into that pointer array . please see below the problem i faced
code:
int cnt1;
char *t_array;
char *f_array;
for(cnt1=0; cnt1<1000; cnt1++)
{
t_array =... (1 Reply)
If one wants to get a start address of a array or a string or a block of memory via a function, there are at least two methods to achieve it:
(1) one is to pass a pointer-to-pointer parameter, like:
int my_malloc(int size, char **pmem)
{
*pmem=(char *)malloc(size);
if(*pmem==NULL)... (11 Replies)
Hi all,
Can anyone provide help with getting the right syntax regarding array/pointers in C in the following code? Can't locate a specific example which clarifies this...
Say I declare a typedef to an array of pointers to some type...
/**
* An array of ptrs to sections
*/
typedef... (4 Replies)
if i create an array of pointers to a structure "struct node" as:
struct node *r;
and create "n" number of "linked lists" and assign it to the various struct pointers r using some function with a return type as structure pointer as:
r=multiplty(.......) /*some parameters*/
is... (2 Replies)
This code is to print out the program name and arguments list one by one:
1 #include<stdio.h>
2
3 void main(int argc, char *argv)
4 {
5 int iCount = 0;
6 while (iCount < argc) {
7 printf("argc:%d\t%s\n",iCount, argv);
8 ... (14 Replies)
Hello,
The purpose of the program is to print a sub string from the prompt inputs. I do not understand why char pointer does not work but char array will for line 40 and Line 41.
./a.out thisisatest 0 8
substring = "thisisat"And my code is:
#include <stdio.h>
#include <stdlib.h>
#include... (29 Replies)
how to copy content of character pointer to character array in c programming..
char *num;
char name=num; (1 Reply)
Discussion started by: zinat
1 Replies
LEARN ABOUT PHP
key
KEY(3) 1 KEY(3)key - Fetch a key from an arraySYNOPSIS
mixed key (array &$array)
DESCRIPTION key(3) returns the index element of the current array position.
PARAMETERS
o $array
- The array.
RETURN VALUES
The key(3) function simply returns the key of the array element that's currently being pointed to by the internal pointer. It does not
move the pointer in any way. If the internal pointer points beyond the end of the elements list or the array is empty, key(3) returns NULL.
EXAMPLES
Example #1
key(3) example
<?php
$array = array(
'fruit1' => 'apple',
'fruit2' => 'orange',
'fruit3' => 'grape',
'fruit4' => 'apple',
'fruit5' => 'apple');
// this cycle echoes all associative array
// key where value equals "apple"
while ($fruit_name = current($array)) {
if ($fruit_name == 'apple') {
echo key($array).'<br />';
}
next($array);
}
?>
The above example will output:
fruit1<br />
fruit4<br />
fruit5<br />
SEE ALSO current(3), next(3).
PHP Documentation Group KEY(3)