const int ldrPin = A0; 
const int relayPin = 7; 
int ldrValue = 0;

void setup() {
  pinMode(relayPin, OUTPUT);
  Serial.begin(9600);
}

void loop() {
  ldrValue = analogRead(ldrPin); 
  Serial.println(ldrValue); 
  
  if (ldrValue < 300) {
    digitalWrite(relayPin, HIGH); 
  } else {
    digitalWrite(relayPin, LOW); 
  }
  
  delay(1000); 
}