const int LEDPin = 13;
const int LDRPin = 2;


void setup() {
  pinMode(LEDPin, OUTPUT);
  pinMode(LDRPin, INPUT);
}

void loop() {
  int value = digitalRead(LDRPin);
  if (value == HIGH){
    digitalWrite(LEDPin, HIGH);
    delay(50);
    digitalWrite(LEDPin, LOW);
    delay(50);
  }
}