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Check the following two functions and explain if method1 and method2 are same?

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#include<stdio.h>
#include<stdlib.h>

int main(void)
{
  int *p
  int size = 10;

  p=(int*)calloc(size,sizeof(int));

  while(i != size)
  {
    *p++=1;       /*    METHOD 1       */
    i++;
  }

  i=0;

  while(i != size)
  {
    i[p] = 1;         /*    METHOD 2    */
    i++;
  }

}    
posted Apr 23, 2017 by Leon Martinović
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1 Answer

+1 vote

Both the methods will result different. In first method pointer "p" is being incremented in every iteration. So once loop exists pointer "p" will be pointing to location which is different from the initial address given by malloc function.
In second method pointer "p" is not being incremented while it is holding the same address allocated at the time of malloc function but in every iteration value "1" is being assigned.

answer Apr 23, 2017 by Harshita
thx__

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