#include <Servo.h>
#define trigPin 13
#define echoPin 12
#define led 11
#define led2 10
#define led3 9

int servoPin = 8;
Servo Servo1;

void setup() {
  Serial.begin (9600);
  Servo1.attach(servoPin);
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
  pinMode(led, OUTPUT);
  pinMode(led2, OUTPUT);
  pinMode(led3, OUTPUT);
}

void loop() {
  long duration, distance;
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  duration = pulseIn(echoPin, HIGH);
  distance = 0.03435 * (duration / 2);
  if (distance > 100) {
    Servo1.write(90);
    delay(1000);
    digitalWrite(led,HIGH);
    digitalWrite(led2,LOW);
    digitalWrite(led3,LOW);
  }
  else if (distance < 101 && distance > 50) {
    digitalWrite(led,LOW);
    digitalWrite(led2,HIGH);
    digitalWrite(led3,LOW);
  }
  else {
    Servo1.write(0);
    delay(1000);
    digitalWrite(led,LOW);
    digitalWrite(led2,LOW);
    digitalWrite(led3,HIGH);
  }
    Serial.print(distance);
    Serial.println(" cm");
  delay(500);
}