// C++ code
//
void setup()
{
  pinMode(3, OUTPUT);
  pinMode(9, OUTPUT);
  pinMode(5, OUTPUT);
  pinMode(A0, INPUT);
  Serial.begin(9600);
}

void loop()
{
  analogReference(INTERNAL);
  int x=analogRead(A0);
  Serial.println(x);
  if(x>=100&&x<250)
   {
    digitalWrite(9, HIGH);
    digitalWrite(5, LOW);
    digitalWrite(3, LOW);
   }
   else if(x>=250&&x<500)
   {
    digitalWrite(3, HIGH);
     digitalWrite(9, LOW);
    digitalWrite(5, LOW);
   }
   else if(x>=500&&x<800){
    digitalWrite(5, HIGH);
     digitalWrite(9, LOW);
    digitalWrite(5, LOW);
   }
}