Explain the output(pointers)

ishandutta2007 · 01-28-2010, 05:38 AM

explain me the output please .As far as my knowledge. a is a character type pointer variable and its size should be 4 bytes irrespective of what its pointing to.but i get a result =50.
*a is the value of a[0] and its size is rightly 1 byte.
but how can the size of that variable change to 4 byte when i just add 7 to it(although i don't store the added result anywhere)

Code:

#include<stdio.h>
int main(){
	char a[50];
	printf("\n%d  ",sizeof(a));
	printf("\n%d  ",sizeof(*a));
	printf("\n%d  ",sizeof(*a+7));
	return 0;
	}

output:

Code:

50
1
4

SigTerm · 01-28-2010, 06:19 AM

Quote:

Originally Posted by ishandutta2007

but i get a result =50.

"a" is an array of 50 chars, so size is correct.
Try this:

Code:

#include<stdio.h>
int main(){
	char a[50];
	char* b = a;
	printf("\n%d  ",sizeof(a));
	printf("\n%d  ",sizeof(b));
	return 0;
}

Dan04 · 01-28-2010, 08:25 AM

*a+7 means (*a)+7. And char+int=int.