#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x27, 16, 2);
int relay = 9;
int led1 = 13;
int led2 = 12;
int ldr = 0;
int nilai;

void setup() {
  lcd.init();
  lcd.backlight();
  Serial.begin(9600);
  pinMode(led1, OUTPUT);
  pinMode(led2, OUTPUT);
  pinMode(relay, OUTPUT);

}

void loop() {
  nilai = analogRead(ldr); 
  Serial.print("nilai : ");
  Serial.println(nilai);
  if (nilai < 300){
    lcd.clear();

    lcd.setCursor(0, 0);
    lcd.print("Lampu Menyala");
    flipflop();
    digitalWrite(relay, HIGH);
  }else{
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("Lampu Mati");
    digitalWrite(led1, LOW);
    digitalWrite(led2, LOW);
    digitalWrite(relay, LOW);
  }
}

void flipflop(){
  digitalWrite(led1, HIGH);
  digitalWrite(led2, LOW);
  delay(200);
  digitalWrite(led1, LOW);
  digitalWrite(led2, HIGH);
  delay(200);
}