void setup() {
  Serial.begin(115200);
  pinMode(12, OUTPUT); //for trigger
  pinMode(14, INPUT); //for echo
   pinMode(21, OUTPUT);
    pinMode(19, OUTPUT);
}

void loop() {
  //Connecting the TRIG PIN
  digitalWrite(12, HIGH);
  delay(100); 
  digitalWrite(12, LOW);

  //Connecting and reading the ECHO PIN
   float duration = pulseIn(14,HIGH);
   int distance = duration*0.034/2 ; //Formula for calculating the distance
   Serial.println(distance);//Printing the distance
   if(distance<=200)
   {
    digitalWrite(21, HIGH);
   }
   else{
    digitalWrite(19, HIGH);
   }
}