Arduino based LOCK/UNLOCK ALARM with LCD

1#include <LiquidCrystal.h>
2
3// initialize the library with the numbers
4  of the interface pins
5LiquidCrystal lcd(8,9,10,11,12,13);
6int new_input_state,old_input_state=LOW;
7void
8  setup() 
9{
10  lcd.begin(16, 2); // set up the LCD's number of columns and rows:
11
12  pinMode(2,INPUT);
13  pinMode(3,OUTPUT);
14  digitalWrite(3,LOW);
15  lcd.clear();
16
17  lcd.print("door is locked");
18  lcd.setCursor(0,1);
19  lcd.print("properly");
20}
21
22void
23  loop() 
24{
25 new_input_state = digitalRead(2);
26 if(new_input_state!=old_input_state)
27
28   {
29      if(new_input_state==HIGH)
30        {
31          lcd.clear();
32
33          lcd.print("door is not");
34          lcd.setCursor(0,1);
35          lcd.print("properly
36  locked");
37          digitalWrite(3,HIGH);
38          tone(4,1000,2000);
39
40        } 
41      else
42         {
43             lcd.clear();
44            lcd.print("door
45  is locked");
46            lcd.setCursor(0,1);
47            lcd.print("properly");
48
49            digitalWrite(3,LOW);
50             noTone(4);
51          } 
52
53        }
54      old_input_state = new_input_state;
55      delay(100);
56  }
57   
58

1#include <LiquidCrystal.h>
2
3// initialize the library with the numbers  of the interface pins
4LiquidCrystal lcd(8,9,10,11,12,13);
5int new_input_state,old_input_state=LOW;
6void  setup() 
7{
8  lcd.begin(16, 2); // set up the LCD's number of columns and rows:
9  pinMode(2,INPUT);
10  pinMode(3,OUTPUT);
11  digitalWrite(3,LOW);
12  lcd.clear();
13  lcd.print("door is locked");
14  lcd.setCursor(0,1);
15  lcd.print("properly");
16}
17
18void  loop() 
19{
20 new_input_state = digitalRead(2);
21 if(new_input_state!=old_input_state)
22   {
23      if(new_input_state==HIGH)
24        {
25          lcd.clear();
26          lcd.print("door is not");
27          lcd.setCursor(0,1);
28          lcd.print("properly  locked");
29          digitalWrite(3,HIGH);
30          tone(4,1000,2000);
31        } 
32      else
33         {
34             lcd.clear();
35            lcd.print("door  is locked");
36            lcd.setCursor(0,1);
37            lcd.print("properly");
38            digitalWrite(3,LOW);
39             noTone(4);
40          } 
41        }
42      old_input_state = new_input_state;
43      delay(100);
44  }   
45