#include <LiquidCrystal.h>


const int rs = 7, en = 6, d4 = 5, d5 = 4, d6 = 3, d7 = 2;
LiquidCrystal lcd(rs, en, d4, d5, d6, d7);


const int trigPin = 9;  
const int echoPin = 10; 


long duration;
float distance;

void setup() {
 
  
 
  
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
 
  
  lcd.begin(16, 2);  
  lcd.print("Distance:");  
}

void loop() {
  
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);

  
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);

  
  duration = pulseIn(echoPin, HIGH);

  
  distance = (duration * 0.03421) / 2;

  
  lcd.setCursor(0, 1);  
  lcd.print("                ");  
  lcd.setCursor(0, 1);  
  lcd.print(distance);   
  lcd.print(" cm");

  
  delay(500);
}