int new_v;
int old_v;
int pin = A0;
int led1 = 2;
int led2 = 3;
int led3 = 4;
int led4 = 5;

int led8 = 8;
int led9 = 9;
void setup() {
  pinMode(pin, INPUT);
  Serial.begin(9600);
  pinMode(led1, OUTPUT);
  pinMode(led2, OUTPUT);
  pinMode(led3, OUTPUT);
  pinMode(led4, OUTPUT);
  pinMode(led8, OUTPUT);
  pinMode(led9, OUTPUT);
}

void loop() {

  digitalWrite(led8, 1);
  delay(200);
  digitalWrite(led8, 0);
  digitalWrite(led9, 1);
  delay(200);
  digitalWrite(led9, 0);
  delay(200);

  new_v = analogRead(pin);
  if (new_v != old_v) {
    Serial.println(new_v);
    old_v = new_v;

  }
  digitalWrite(led1, (old_v >= 250) );
  digitalWrite(led2, (old_v >= 500) );
  digitalWrite(led3, (old_v >= 750) );
  digitalWrite(led4, (old_v >= 1000) );
}