Build your own parking space!

1#include <Wire.h> 
2#include <Servo.h>
3#include <LiquidCrystal_I2C.h>
4//  the libaries for 16x2 I2C is from github:
5// https://github.com/fdebrabander/Arduino-LiquidCrystal-I2C-library
6
7//  Set the LCD address to 0x27 for a 16 chars and 2 line display
8LiquidCrystal_I2C  lcd(0x27, 16, 2);
9// Pins that recives the analoge signal from the ldr to arduino
10const  int ldrPin1 = A0;
11const int ldrPin2 = A1;
12const int ldrPin3 = A2; 
13const  int ldrPin4 = A3;
14const int ldrPin5 = A4; 
15Servo myservo;
16int re = 4; //count  the car place remain
17
18void setup() {
19  // put your setup code here, to  run once:
20  lcd.begin();
21  lcd.backlight();
22  lcd.setCursor(0,0);
23  lcd.print("Spaces  available");
24  
25  myservo.attach(9); // attach the servo to our servo object
26  myservo.write(90); // set the servo motor speed to zero
27}
28void loop() {
29  // put your main code here, to run repeatedly:
30  re = 4; // update the value
31  lcd.setCursor(0,1); // set the cursor for the lcd scream to the second row
32  delay(20);
33  int ldrStatus1 = analogRead(ldrPin1); // read the value from the  pin
34  int ldrStatus2 = analogRead(ldrPin2);
35  int ldrStatus3 = analogRead(ldrPin3);
36  int ldrStatus4 = analogRead(ldrPin4);
37  int ldrStatus5 = analogRead(ldrPin5);
38  
39  if (ldrStatus2 < 300) { // *important: change the variable for you own ldr
40    re--;
41  }
42  if (ldrStatus3 < 300) {
43    re--;
44  }
45  if (ldrStatus4  < 300) {
46    re--;
47  }
48  if (ldrStatus5 < 300) {
49    re--;
50  }
51  if (ldrStatus1 < 300) { //check if there is car trying to enter
52    if(re ==  0){ // the parking place is full
53      lcd.print("              ");// clear  the screem by rewrite on it
54      lcd.setCursor(0,1);
55      lcd.print(" Bad  Luck  ");
56      delay(3000); // display it on the screem for 3 sec
57      lcd.setCursor(0,1);
58      lcd.print("               ");
59    }
60    else{
61      lcd.clear();  // clear the whole screem
62      for(int i=-7; i<17; i++){ // let the message  roll though the screem
63        lcd.clear();
64        lcd.setCursor(i,0);
65        lcd.print("Welcome             ");
66        delay(200);
67      }
68      myservo.write(45); // 360 degree sg90 turn clockwise
69      delay(200);  // around 90 degree under this time delay
70      myservo.write(90);// stop
71      delay(5000); // wait 5 sec let the car pass
72      myservo.write(135);//  360 degree sg90 turn anticlockwise
73      delay(200);
74      myservo.write(90);
75    }
76    lcd.setCursor(0,0);
77    lcd.print("Spaces available");
78    lcd.setCursor(0,1);
79  }
80  lcd.print(re); // print the space remain
81}