#include <stdio.h>
#define MAX_LEN 20

int main() {
    char a[MAX_LEN]="hello";
    char *ptr=a;
    printf("%s",ptr);
    printf("\nsize of ptr = %ld",sizeof(ptr));//just the size of pointer//this is not value
    printf("\nsize of *ptr = %ld",sizeof(*ptr));//just sz of char//this one is not address of pointer
    
    int b=10;
    
    int *pt=&b;
    int *p=&b;
    
    int c=25;
    pt=&c;
    
    pt=p;//value will be copied
    printf("\nsize of pt = %ld",sizeof(pt));
    *pt=*p;//address od pointer will be copied
    printf("\nsize of *pt = %ld",sizeof(*pt));
    /*here we use *pt to change the value or take value 
    of the value of str or int
    * in *pt acts as a key to a loacker(value pt) */
    printf("\n%d",*pt);
}
/*
why used % ld in size of int,double,float program?

The sizeof() operator returns a long unsigned integer so the correct format
specifier is %lu.
%ld is for signed long integers (which can have a negative value).
The return value of sizeof() is either 0 or some positive value, never negative.
*/