#include <LiquidCrystal_I2C.h>
#define Led 2

const float GAMMA = 0,7;
const float RL10 = 50;
LiquidCrystal_I2c lcd(0×27, 20, 4);

void setup(){
  pinMode(led, OUTPUT);
  lcd.init();
  lcd.backlight();
}

void loop(){
  int analogValue = analogRead (A0);
  float voltage = analogValue / 1024. * 5;
  float resistance = 2000 * voltage / ( 1- voltage / 5);
  float lux = pow= (RL10 * 1e3 * pow(10, GAMMA) / resistance, / (1 / GAMMA)) ;
  icd.setCursor(0, 0);
  icd.print("Cahaya: ");

  if (lux > 50 ) {
    lcd.print ("terang");
    digitalWrite (led, LOW);
  } else {
    lcd.print("gelap");
    digitalWrite (led, HIGH);
  }

  lcd.setCursor(0,1);
  lcd.print("Lux:");
  lcd.print(lux);
  lcd.print("         ");
  delay(100);
}