const int sensorMin=0;
const int sensorMax=600;
int ledPin=10;

void setup() {
//initialize serial communication:
Serial.begin(9600);
pinMode(ledPin, OUTPUT);
digitalWrite(ledPin, HIGH);
}

void loop() {
  //read the sensor:
  int sensorReading=analogRead(A0);
  // map the sensor range to range of four options:
  int range=map(sensorReading,sensorMin,sensorMax,0,3);
//do something different depending on the range value:
switch (range) {
case 0: //your hand is on the sensor
Serial.println("dark");
digitalWrite(ledPin, LOW);
break;
case 1: //your hand is close to the sensor
Serial.println("dim");
digitalWrite(ledPin, LOW);
break;
case 2: //your hand is a few inches from the sensor
Serial.println("medium");
digitalWrite(ledPin, LOW);
break;
case 3: //your hand is nowhere near the sensor
Serial.println("bright");
digitalWrite(ledPin, HIGH);
break;

}

delay(100); //delay in between reads for stability
}