How to make digital distance meter

1
2#include <LiquidCrystal.h>
3 
4#define trigger 18
5#define echo  19
6 
7LiquidCrystal lcd(2,3,4,5,6,7);
8 
9float time=0,distance=0;
10  
11void setup()
12{
13 lcd.begin(16,2);
14 pinMode(trigger,OUTPUT);
15 pinMode(echo,INPUT);
16  lcd.print(" Ultra Sonic ");
17 lcd.setCursor(0,1);
18 lcd.print(" Distance  Meter ");
19 delay(8000);
20 lcd.clear();
21 lcd.print(" Shashwat__Raj ");
22  delay(5000);
23}
24 
25void loop()
26{
27 lcd.clear();
28 digitalWrite(trigger,LOW);
29  delayMicroseconds(2);
30 digitalWrite(trigger,HIGH);
31 delayMicroseconds(10);
32  digitalWrite(trigger,LOW);
33 delayMicroseconds(2);
34 time=pulseIn(echo,HIGH);
35  distance=time*340/20000;
36 lcd.clear();
37 lcd.print("Distance:");
38 lcd.print(distance);
39  lcd.print("cm");
40 lcd.setCursor(0,1);
41 lcd.print("Distance:");
42 lcd.print(distance/100);
43  lcd.print("m");
44 delay(1000);
45}
46