const int trigP=18;
const int echoP=5;
long duration;
int distance;
void setup() 
{
pinMode(trigP,OUTPUT);
pinMode(echoP,INPUT);
Serial.begin(9600); }
void loop() { 
digitalWrite(trigP,LOW);
delayMicroseconds(2);
digitalWrite(trigP,HIGH);
delayMicroseconds(10);
digitalWrite(trigP,LOW);
duration=pulseIn(echoP,HIGH);
distance=duration*0.034/2;
Serial.print("Distance=");
Serial.println(distance);
delay(500);
}