const int numReadings = 10;

int readings[numReadings];      // the readings from the analog input
int index = 0;                  // the index of the current reading
int total = 0;                  // the running total
int average = 0;
int micPin = A0;
int ledPin = 6;

void setup() {
  // put your setup code here, to run once:
   // initialize serial communication with computer:
  pinMode(micPin, INPUT);
  pinMode(ledPin, OUTPUT);
  digitalWrite(ledPin, LOW);
  Serial.begin(9600);                   
  // initialize all the readings to 0: 
  for (int thisReading = 0; thisReading < numReadings; thisReading++)
    readings[thisReading] = 0;   

}

void loop() {
  // put your main code here, to run repeatedly:
 // subtract the last reading:
  total= total - readings[index];         
  // read from the sensor:  
  readings[index] = analogRead(micPin); 
  // add the reading to the total:
  total= total + readings[index];       
  // advance to the next position in the array:  
  index = index + 1;                    

  // if we're at the end of the array...
  if (index >= numReadings)              
    // ...wrap around to the beginning: 
    index = 0;                           

  // calculate the average:
  average = total / numReadings;         
  // send it to the computer as ASCII digits
  
  Serial.println(average);   
  delay(1);        // delay in between reads for stability  

  int newAvg = map(average, 0, 1023, 0, 255);
  analogWrite(ledPin, newAvg); 
}