#include <stdio.h>

unsigned PORTA = 0;

typedef struct
{
 unsigned bit_0 : 1;
 unsigned bit_1 : 1;
 unsigned bit_2 : 1;
 unsigned bit_3 : 1;
 // ...
} bitset_t;

#define LED ((bitset_t *)(&PORTA))->bit_3
#define ON 1
#define OFF 0

void foo()
{
 LED = ON;
}

int main(void) {
	foo();
	printf("%i\n", PORTA);
	// your code goes here
	return 0;
}