//Car-parking IOT app

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


void setup() 
{ // put your setup code here, to run once:
pinMode(trigpin, OUTPUT);
pinMode(echopin, INPUT);
pinMode(Buzzpin,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(Buzzpin,1100,300);   //1100 is frequency and 300 is time in msec
    delay(100);
    tone(Buzzpin,700,100);
    delay(200);
    tone(Buzzpin,800,1700);
    delay(200);
  }
}