#define echoPin 2 
#define trigPin 3 
long duration;
int distance;
void setup() {
 Serial.begin(9600);
 pinMode(trigPin, OUTPUT);
 pinMode(echoPin, INPUT);
}

void loop() {
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  duration = pulseIn(echoPin,HIGH);
  distance = (duration * 0.034 / 2);
  Serial.print("Distance :");
  Serial.print(distance);
  Serial.println("cm");
  delay(1000);
}