#define trig 16
#define echo 18

void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
  pinMode(2, OUTPUT);
  pinMode(trig,OUTPUT);
  pinMode(echo,INPUT);
}

void loop() {
  // put your main code here, to run repeatedly:
  digitalWrite(2,HIGH);
  delay(1000); // this speeds up the simulation
  digitalWrite(2,LOW);
  delay(1000);}
  void loop1(){

  digitalWrite(trig, LOW);
  delay(2000);
  digitalWrite(trig, HIGH);
  delay(10000);
  digitalWrite(trig, LOW);
  long duration = pulseIn(echo,HIGH);
  float distance = (duration*0.5*343)/10000;
  Serial.println(distance,3);
}