// Define pin numbers
const int ldrPin = A0;      // LDR connected to analog pin A0
const int relayPin = 3;     // Relay control connected to digital pin 3

// Set a light threshold (adjust this value as needed)
const int lightThreshold = 500; // Change this value based on your environment

void setup() {
  // Initialize the relay pin as an output
  pinMode(relayPin, OUTPUT);
  
  // Start with relay off
  digitalWrite(relayPin, HIGH);
  
  // Start serial communication for debugging
  Serial.begin(9600);
}

void loop() {
  // Read the value from the LDR
  int ldrValue = analogRead(ldrPin);
  
  // Print the LDR value for debugging
  Serial.print("LDR Value: ");
  Serial.println(ldrValue);
  
  // Check if the LDR value is below the threshold
  if (ldrValue < lightThreshold) {
    // Activate the relay
    digitalWrite(relayPin, LOW);
  } else {
    // Deactivate the relay
    digitalWrite(relayPin, HIGH);
  }
  
  // Small delay before the next reading
  delay(500);
}