/*
Sketch uses 1118 bytes (3%) of program storage space. Maximum is 32256 bytes.
Global variables use 9 bytes (0%) of dynamic memory, leaving 2039 bytes for local variables. Maximum is 2048 bytes.
*/

#define PIN_A 2
#define PIN_B 3
#define PIN_C 4

void setup() {
  // Initial pin mode setup
  pinMode(PIN_A, INPUT);
  pinMode(PIN_B, INPUT);
  pinMode(PIN_C, INPUT);
}

void loop() {
  light_led(PIN_A, PIN_B, PIN_C); // LED1: A -> B
  delay(200);
  light_led(PIN_B, PIN_A, PIN_C); // LED2: B -> A
  delay(200);
  light_led(PIN_A, PIN_C, PIN_B); // LED3: A -> C
  delay(200);
  light_led(PIN_C, PIN_A, PIN_B); // LED4: C -> A
  delay(200);
  light_led(PIN_B, PIN_C, PIN_A); // LED5: B -> C
  delay(200);
  light_led(PIN_C, PIN_B, PIN_A); // LED6: C -> B
  delay(200);
}

// Function to turn on one LED
// After each function call the IO pins are reset as INPUTS
void light_led(uint8_t high_pin, uint8_t low_pin, uint8_t z_pin) {
  // Set pins as input to start (disables all LEDs)
  pinMode(PIN_A, INPUT);
  pinMode(PIN_B, INPUT);
  pinMode(PIN_C, INPUT);

  // Apply drive to desired pins
  pinMode(high_pin, OUTPUT);
  pinMode(low_pin, OUTPUT);
  digitalWrite(high_pin, HIGH);
  digitalWrite(low_pin, LOW);
}