int threshold=0;
void setup() {
  pinMode(A0, INPUT);
  pinMode(4,OUTPUT);
  Serial.begin(9600);
  
}

void loop() {
  threshold=analogRead(A0);
  Serial.println(threshold);
  delay(500);
  if(threshold>450){
    digitalWrite(4,1);
    
  }
  else{
    digitalWrite(4,0);
  }

}