// Define DIP switch and LED bar graph pins
const int dipSwitchPins[] = {2, 3, 4, 5}; // Pins connected to the DIP switch
const int numDipSwitches = 4; // Number of switches in the DIP switch
const int ledPins[] = {6, 7, 8, 9}; // Pins connected to the LEDs in the bar graph
const int numLEDs = 4; // Number of LEDs in the bar graph

void setup() {
  // Set DIP switch pins as inputs with internal pull-up resistors
  for (int i = 0; i < numDipSwitches; i++) {
    pinMode(dipSwitchPins[i], INPUT_PULLUP);
  }

  // Set LED bar graph pins as outputs
  for (int i = 0; i < numLEDs; i++) {
    pinMode(ledPins[i], OUTPUT);
  }
}

void loop() {
  // Read the state of the DIP switch
  for (int i = 0; i < numDipSwitches; i++) {
    int switchState = digitalRead(dipSwitchPins[i]);

    // Illuminate corresponding LED if the switch is ON
    if (switchState == LOW) {
      illuminateLEDs(i);
    } else {
      turnOffLEDs();
    }
  }
}

void illuminateLEDs(int switchIndex) {
  // Turn on LEDs up to the specified switch index
  for (int i = 0; i <= switchIndex; i++) {
    digitalWrite(ledPins[i], HIGH);
  }
}

void turnOffLEDs() {
  // Turn off all LEDs in the bar graph
  for (int i = 0; i < numLEDs; i++) {
    digitalWrite(ledPins[i], LOW);
  }
}