int photoPin = A0;
int redLedPin = 9;
int greenLedPin = 10;
float  fixedResistor = 10000.0;
int dt = 1000;

void setup(){
  Serial.begin(9600);
  pinMode(photoPin, INPUT);
  pinMode(redLedPin, OUTPUT);
  pinMode(greenLedPin, OUTPUT);
}

void loop(){
  int photoValue = analogRead(photoPin);

  // Conversion of analogValue which is between 0 to 1023 into analog voltagr

float photoResistance = (fixedResistor * (1023.0 - photoValue)) / photoValue;
float brightness = map(photoResistance,0,10000,0,255);

if(photoValue >500){
  digitalWrite(greenLedPin, HIGH);
  digitalWrite(redLedPin, LOW);
}
else{
  digitalWrite(greenLedPin, LOW);
  digitalWrite(redLedPin, HIGH);
}
Serial.print(" Photo Resistor Value = ");
Serial.print(photoValue);
Serial.print(",");
Serial.print(" Resistance = ");
Serial.print(photoResistance);
Serial.print(", Brighness Level = ");
Serial.println(brightness);
delay(dt);
}