int sensorValue = 0;
int sensorPin = A0;
int ELPin = 0;
int pulse = 0;
void setup()
{
}
void loop()
{
   int x = 1;
   int Aread = analogRead(sensorPin)/128;
   int z = x * Aread;
   for (int i = 0; i > -1; i = i + z)
   {
      analogWrite(ELPin, i);
      if (i == 255) x = -1;
      delay(10);
   }
}