#include <avr/io.h>
#define led_pin (1 << PB2)
#define button_pin (1 << PA3)


int main(void) {
	// Configure led_pin as an output.
	DDRB |= led_pin;

	DDRA &= ~button_pin;

    // Activate button_pin's pullup resistor.
	PORTA |= button_pin;

   while (1) {

   	  if(PINA & button_pin) {
   	  	PORTB &= ~led_pin;

   	  } else{
   	  	PORTB |= led_pin;

   	  }

   }
}