const  int LDR = 4;  // 
const int  LED = 5; //
int input_val  = 0;
void setup()  {
  Serial.begin(9600);
  pinMode(LED, OUTPUT);
}
  void loop () {
    input_val = analogRead(LDR);
    Serial.print("LDR Value is : ");
    Serial.print(input_val);
    delay(1000);
    if (input_val>800)
  {
   digitalWrite(LED,HIGH);
   delay(5000);
  }
  else{
    digitalWrite(LED,LOW);
    delay(5000);
  }
  }