void setup()
{
  DDRB |= (1 << PB3) | (1 << PB2) | (1 << PB1) | (1 << PB0); // setting the Data Direction Register of PORTB
  PORTB |= (1 << PB4) | (1 << PB5); // activating pull ups on PB4 and PB5
  DDRD |= (1 << PD7); // setting the Data Direction Register of PORTD
}

void loop()
{
  if ((PINB & (1 << PB4)) == 0 || (PINB & (1 << PB5)) == 0)
    PORTD = PORTD | (1 << PD7);   // setting PD7
  else
    PORTD = PORTD & ~(1 << PD7);  // clearing PD7
}