int trig = 10;
int echo = 9;
float duration;

void setup() {
  pinMode(10, INPUT);
  pinMode(9,OUTPUT);
  Serial.begin(9600);
}

void loop() {
 
 digitalWrite(trig, HIGH);
 delayMicroseconds(10);
 digitalWrite(trig, LOW);

 duration = pulseIn(echo,HIGH);
 Serial.println(duration/58);

 delay(1000);

}