Read Ultrasonic AN Distance in CM

const int anPin = 0;
long anVolt, cm;

void setup() {
   Serial.begin(9600);
}

void read_sensor(){
   anVolt = analogRead(anPin);
   cm = anVolt/2;
}

void print_range(){ 
   Serial.print(“Range = ”);
   Serial.print(cm);
   Serial.print(” cm “);
   Serial.print('\n'); 
}
 
void loop() {  
   read_sensor();
   print_range();
   delay(100);
}