void pointer and different type value

Question

in this code I try test return different type declared variable, but wonderful things in out put :
char c = 'a';
ptr = &c;
printf("void ptr points to %c", *((int *)ptr));

is -> 'a'

and for

int x = 33;
printf("void ptr points to %d\n", *((char *)ptr));
is -> 33

why?

https://code.sololearn.com/cIkHV9MrHM7N/?ref=app

Answer 1

To extend swim's wonderful explanation,

Remember that different types are the representation of containers of different sizes. An int is 4 bytes. A char is 1 byte. What happens when you do

int x = 33;
char* ptr = &x;

is that the pointer points to the first byte of x and tries to treat it as a char. Whatever wonderful things that would happen later is dependent on the compiler implementation. This leads to our best friend, undefined behaviour.