How do I assign pa=ptr

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//assigning one  string  to other string  using  pointer
int main(){
char ch[] = "Hello";
char pa[10];
char *ptr;
ptr=ch;
          //HERE WE WILL BE TAKING  WHILE LOOP (*ptr!='\0')

pa=ptr;
pa++;
ptr++

can  we  assign in these manner or else we  have to take  pa[some variable]=ptr; or *pa=*ptr;or pa=ptr;
and  while incrementing can we take pa++ or else pa+1;or pa[some  variable]++;
in last *pa='\0';or pa[some variable]='\0';end string

What I have tried:

i  have  tried and  got  output  but confuse
pa[some variable]=*ptr;
pa+1;
pa[some variable]='\0';

Posted 18-Sep-22 19:54pm

sundresjh

Updated 18-Sep-22 20:15pm

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Comments

Richard MacCutchan 19-Sep-22 4:41am

This is your third question on this subject (the first one back in May) and you still do not seem to understand the difference between an array (which is a fixed address) and a pointer which is a variable that can be modified.

2 solutions

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OriginalGriff · Answer 1 · 2022-09-18T20:07:00

Um. That's confused code!
You create two char arrays:

C

char ch[] = "Hello";
char pa[10];

And by the C language definition, the name of an array is a pointer to the first element, so both ch and pa are pointers to char values.
Then you create a char pointer and set it to one of them:

C

char *ptr;
ptr=ch;

But then you overwrite one of the array pointers with the other:

C

pa=ptr;

Which means that you no longer have anything which can access the second array data!

If you are trying to copy data from one array to the other using pointers, then you need to create two new pointers so that you can "walk" them through the arrays:

C

char inp[] = "Hello World!";
char out[13];
char *pinp = inp;
char *pout = out;
for (int i = 0; i < 13; i++)
   {
   *pout++ = *pinp++;
   }
printf("%s\n", out);

CPallini · Answer 2 · 2022-09-18T20:15:00

Solution 2

Try

C

#include <stdio.h>

int main()
{
  char s[] = "Hello";
  char a[10];
  char *p;

  p = s; // here 'p' is just an alias of 's'

  printf("s = %p, p = %p\n", a, p);

  printf("content of s, pointed by p: '%s'\n", p);


  // now let's make a copy of 's' in 'a'
  int n;
  for (n=0; *p; ++n, ++p)
  {
    a[n] = *p;
  }
  a[n] = '\0';

  printf("content of a: '%s'\n", a);

  return 0;
}

Note, the C library provides the strcpy function, for the very task of copying a string:

C

#include <stdio.h>
#include <string.h>

int main()
{
  char s[] = "Hello";
  char a[10];

  strcpy(a,s);

  printf("content of a: '%s'\n", a);

  return 0;
}

Posted 18-Sep-22 20:15pm

CPallini

Comments

merano99 19-Sep-22 19:32pm

It would be good to query the limit of a[] as well.

CPallini 20-Sep-22 2:12am

Definitely. Neither my code nor strcpy does it.

sundresjh 22-Sep-22 23:45pm

//I will be learning look forward learn from mistake
for (n=0; *p; ++n, ++p)Here in condition what does *p means
{
a[n] = *p;
} how its working please can anyone explain

CPallini 23-Sep-22 1:52am

The condition in place (*p) is:
"iterate until the character pointed by p is NOT the string terminator (i.e. zero)".

How do I assign pa=ptr

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How do I assign pa=ptr

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