void setup() {
  pinMode(2, OUTPUT);
  pinMode(3, OUTPUT);
  pinMode(4, OUTPUT);
  pinMode(5, OUTPUT);
  pinMode(6, OUTPUT);
  pinMode(A0, INPUT);
 Serial.begin(9600);
}

void loop() {
  int value = analogRead(A0);
  int value1 = map(value,0,1023,0,4);
  Serial.println(value1);

  if (value1 >= 0){
    digitalWrite(2, HIGH);
  }
  else{
    digitalWrite(2, LOW);
  }

    if (value1 >= 1){
    digitalWrite(3, HIGH);
  }else{
    digitalWrite(3, LOW);
  }

    if (value1 >= 2){
    digitalWrite(4, HIGH);
  }else{
    digitalWrite(4, LOW);
  }

    if (value1 >= 3){
    digitalWrite(5, HIGH);
  }else{
    digitalWrite(5, LOW);
  }

    if (value1 >= 4){
    digitalWrite(6, HIGH);
  }else{
    digitalWrite(6, LOW);
  }

}