const int ledPins[] = {2, 4, 5, 18, 17, 16, 21, 19, 32};  
const int numLEDs = 9;

void leftToRight(void *pvParameters);
void rightToLeft(void *pvParameters);
void oddsAreEven(void *pvParameters);

void setup() {
  for (int i = 0; i < numLEDs; i++) {
    pinMode(ledPins[i], OUTPUT);
  }

  xTaskCreate(leftToRight, "LeftToRight", 1000, NULL, 1, NULL);
  xTaskCreate(rightToLeft, "RightToLeft", 1000, NULL, 1, NULL);
  xTaskCreate(oddsAreEven, "OddsAreEven", 1000, NULL, 1, NULL);
}



void leftToRight(void *pvParameters) {
  while (1) {
    for (int i = 0; i < 3; i++) {
      digitalWrite(ledPins[i], HIGH);
      delay(500);
      digitalWrite(ledPins[i], LOW);
    }
  }
}

void rightToLeft(void *pvParameters) {
  while (1) {
    for (int i = 5; i >= 3; i--) {
      digitalWrite(ledPins[i], HIGH);
      delay(500);
      digitalWrite(ledPins[i], LOW);
    }
  }
}

void oddsAreEven(void *pvParameters) {
  while (1) {
    // Turn on odds
    for (int i = 6; i < numLEDs; i += 2) {
      digitalWrite(ledPins[i], HIGH);
    }
    delay(500);
    // Turn off odds
    for (int i = 6; i < numLEDs; i += 2) {
      digitalWrite(ledPins[i], LOW);
    }
    
    // Turn on evens
    for (int i = 7; i < numLEDs; i += 2) {
      digitalWrite(ledPins[i], HIGH);
    }
    delay(500);
    // Turn off evens
    for (int i = 7; i < numLEDs; i += 2) {
      digitalWrite(ledPins[i], LOW);
    }
  }
}

void loop() {
 
}