int trigpin = 3;
int echopin = 2;
int Time;
int Distance;
int buzzerpin = 9;

void setup() {
  // put your setup code here, to run once:
  pinMode(trigpin, OUTPUT);
  pinMode(echopin, INPUT);
  pinMode(buzzerpin, OUTPUT);
}

void loop() {
  // put your main code here, to run repeatedly:
  digitalWrite(trigpin, LOW);
  digitalWrite(trigpin, HIGH);
  digitalWrite(trigpin, LOW);
  Time = pulseIn(echopin, HIGH);
  Distance = Time * 0.0172;

  if(Distance>30){
    digitalWrite(11, HIGH);
    digitalWrite(13, LOW);
  }

  else{
    digitalWrite(11, LOW);
    digitalWrite(13, HIGH);
    tone(buzzerpin, 1100, 300);
    delay(100);
    tone(buzzerpin, 700, 100);
    delay(200);
    tone(buzzerpin, 800, 1700);
    delay(200);
  }
}