const int trig=26;
const int echo=12;
float duration;
float distance;

void setup() {
  Serial.begin(115200);
  pinMode(trig, OUTPUT);
  pinMode(echo, INPUT);
}
float getdistance(){
  digitalWrite(trig, LOW);
  delayMicroseconds(2);
  digitalWrite(trig, HIGH);
  delayMicroseconds(10);
  digitalWrite(trig, HIGH);
  duration=pulseIn(echo,HIGH);
  int distance=duration*0.03405/2;
  Serial.println(distance);
}
void loop() {
 distance=getdistance();
 Serial.println("distance:"+String(distance)); 
 delay(3000);
}