int trigpin=11;
int echopin=12;
long duration, cm, inches;
void setup() {
Serial.begin(9600);
pinMode(trigpin, OUTPUT);
pinMode(echopin, INPUT);
}
void loop() {
digitalWrite(trigpin,LOW);
delayMicroseconds(5);
digitalWrite(trigpin, HIGH);
delayMicroseconds(10);
digitalWrite(trigpin, LOW);
pinMode(echopin, INPUT);
duration=pulseIn(echopin, HIGH);
cm=(duration/2)/29.1;
inches=(duration/2)/74;
Serial.print(inches);
Serial.print("in, ");
Serial.print(cm);
Serial.print("cm");
Serial.println();
delay(250);
}