// Define pin numbers for LEDs
const int ledPins[] = {13, 12, 11, 10}; // 4-bit binary counter

// Define pin numbers for push buttons
const int incButtonPin = 2; // Increment button
const int decButtonPin = 3; // Decrement button

// Variables to store the current state of the counter and button states
int counter = 0;
int lastIncButtonState = LOW;
int lastDecButtonState = LOW;




void setup() {
  // put your setup code here, to run once:
  // Initialize LED pins as outputs
  for (int i = 0; i < 4; i++) {
    pinMode(ledPins[i], OUTPUT);
  }

  // Initialize button pins as inputs
  pinMode(incButtonPin, INPUT);
  pinMode(decButtonPin, INPUT);

 

}

void loop() {
  // put your main code here, to run repeatedly:
  // Read the current state of the buttons
  int incButtonState = digitalRead(incButtonPin);
  int decButtonState = digitalRead(decButtonPin);

  // Check if the increment button is pressed
  if (incButtonState == HIGH && lastIncButtonState == LOW) {
    counter++;
    if (counter > 15) { // Reset counter if it exceeds 4-bit limit
      counter = 0;
    }
    updateLEDs();
  }

  // Check if the decrement button is pressed
  if (decButtonState == HIGH && lastDecButtonState == LOW) {
    counter--;
    if (counter < 0) { // Reset counter if it goes below 0
      counter = 15;
    }
    updateLEDs();
  }

  // Update the last button states
  lastIncButtonState = incButtonState;
  lastDecButtonState = decButtonState;

  // Small delay to debounce the buttons
  delay(50);
}
  // Function to update the LEDs based on the current counter value
void updateLEDs() { 
    for (int i = 0; i < 4; i++) {
    digitalWrite(ledPins[i], (counter >> i)& 0x01);
    
  }
}