#include "LiquidCrystal_I2C.h"
#include  <Wire.h>
LiquidCrystal_I2C lcd(0x27,  20, 4);

const int trigPin = 9;
const int echoPin = 10;
float duration, distance;

void hcsr04() {
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  duration = pulseIn(echoPin, HIGH);
  distance = (duration*.0343)/2;
  Serial.print("Distance: ");
  Serial.println(distance);
  delay(100);
  lcd.setCursor(0,3);
  lcd.print("Distance: ");
  lcd.print(distance);
}
void setup() {  
  lcd.init();  
  lcd.backlight();
  Serial.begin(9600);
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
}
void loop() {  
  delay(1000);  
  lcd.setCursor(0,0);  
  lcd.print("");  
  lcd.setCursor(0,1);  
  lcd.print("");  
  hcsr04();
}