#include <Servo.h>
#include <Ultrasonic.h>

Servo servo;

Ultrasonic sensor(7,8);

void setup()
{

  Serial.begin(9600);

  pinMode(4, OUTPUT);
  pinMode(5, OUTPUT);
  pinMode(6, OUTPUT);
  pinMode(7, OUTPUT); 

  pinMode(8, INPUT);
  
  servo.attach(3, 500, 2500);
  servo.write(90);
}

void loop()
{
  int d;

  d = sensor.read();
 
  Serial.println(d);
  
  if (d < 10) 
  {
    servo.write(0);
    digitalWrite(4, HIGH);
    digitalWrite(5, LOW);
    digitalWrite(6, LOW);
  }
  else if (d >= 10 && d < 50) 
  {
    servo.write(90);
    digitalWrite(4, LOW);
    digitalWrite(5, HIGH);
    digitalWrite(6, LOW);
  }
  else if (d >= 50) 
  {
    servo.write(180);
    digitalWrite(4, LOW);
    digitalWrite(5, LOW);
    digitalWrite(6, HIGH);
  }
  delay(10); // Delay a little bit to improve simulation performance
}