Entrada analogica

int sensorPin = 0;   
int ledPin =7;     
int sensorValue = 0; 
void setup() {
  pinMode(ledPin, OUTPUT);
}

void loop() {
  sensorValue = analogRead(sensorPin); 
  digitalWrite(ledPin, HIGH);
  delay(sensorValue);       
  digitalWrite(ledPin, LOW);
  delay(sensorValue);               
}