int LED=3;
int ldr = A0;
int valorldr = 0;

void setup() {
  // put your setup code here, to run once:
Serial.begin(9600);
pinMode(LED,OUTPUT);
}

void loop() {
 
  valorldr = analogRead(ldr);
  Serial.println(valorldr);
  delay(500);
  if(valorldr<=350 ){
    digitalWrite(LED,HIGH);
  }

}