void setup() {
  // put your setup code here, to run once:
 pinMode(2, OUTPUT);
 pinMode(3, OUTPUT);
 pinMode(4, OUTPUT);
}

void loop() {
  // put your main code here, to run repeatedly:
  if (analogRead(A0) <= 341){
    digitalWrite(2,HIGH);
    digitalWrite(3,LOW);
    digitalWrite(4,LOW);
  }
  else if (analogRead(A0) >= 682){
    digitalWrite(2,LOW);
    digitalWrite(3,LOW);
    digitalWrite(4,HIGH);
  }
  else
  {
    digitalWrite(2,LOW);
    digitalWrite(3,HIGH);
    digitalWrite(4,LOW);
  }
}