#define LDR_PIN 35


const float GAMMA = 0.7;
const float RL10 = 50;

void setup() {

     //make analog pin A0 as input
  pinMode(LDR_PIN, INPUT);
  //Serial.begin(9600);   //initialize serial monitor

}

void loop() {

  int analogValue = analogRead(LDR_PIN);
  float voltage = analogValue / 1024. * 5;
  float resistance = 2000 * voltage / (1 - voltage / 5);
  float lux = pow(RL10 * 1e3 * pow(10, GAMMA) / resistance, (1 / GAMMA));
  
  Serial.println(lux);


}