const int TRIG_PIN = 2;
  const int ECHO_PIN = 4;
  long duration,distance;
  void setup() {
  Serial.begin(115200);
  // put your setup code here, to run once:
  pinMode(TRIG_PIN, OUTPUT);
  pinMode(ECHO_PIN, INPUT);
  }
  void loop(){
  distance = getDistanceInCentimrter();
  Serial.println("Distance = "+ String(distance));   
  delay(1000);
  }
  long getDistanceInCentimrter() {
  digitalWrite(TRIG_PIN, LOW);    
  delayMicroseconds(2);
  digitalWrite(TRIG_PIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN, LOW);  
  duration = pulseIn(ECHO_PIN, HIGH);
  return (duration * 0.034 /2+1);  
  }