---

#define GREEN_LED 2
#define YELLOW_LED 3
#define BLUE_LED 4

#define BTN1 A0
#define BTN2 A1
#define BTN3 A2

void setup()
{
  pinMode(GREEN_LED, OUTPUT);
  pinMode(YELLOW_LED, OUTPUT);
  pinMode(BLUE_LED, OUTPUT);

  pinMode(BTN1, INPUT);
  pinMode(BTN2, INPUT);
  pinMode(BTN3, INPUT);
}

void loop()
{
  int count = 0;

  if (digitalRead(BTN1) == HIGH)
    count++;

  if (digitalRead(BTN2) == HIGH)
    count++;

  if (digitalRead(BTN3) == HIGH)
    count++;

  if (count == 1)
  {
    digitalWrite(GREEN_LED, HIGH);
    digitalWrite(YELLOW_LED, LOW);
    digitalWrite(BLUE_LED, LOW);
  }
  else if (count == 2)
  {
    digitalWrite(GREEN_LED, LOW);
    digitalWrite(YELLOW_LED, HIGH);
    digitalWrite(BLUE_LED, LOW);
  }
  else if (count == 3)
  {
    digitalWrite(GREEN_LED, LOW);
    digitalWrite(YELLOW_LED, LOW);
    digitalWrite(BLUE_LED, HIGH);
  }
  else
  {
    digitalWrite(GREEN_LED, LOW);
    digitalWrite(YELLOW_LED, LOW);
    digitalWrite(BLUE_LED, LOW);
  }
}