Electronic Voting Machine

/*The given code is a basic implementation of electronic voting machine .The design given below is for three teams but can be further extended for more teams
In this code very time a voter castes his vote the response is recored and a new session begins where another voter can cast his vote.
the whole thing ends when the final offical encharge presses the stop button for ending the voting procedure and displaying the winner
In this code few isr's have been used for button triggers*/
 /* THE CIRCUIT:
 ==========================================
 LCD pin              Connect to
 ------------------------------------------
 01 - GND             GND, pot
 02 - VCC             +5V, pot
 03 - Contrast        Pot wiper
 04 - RS              Pin8 (P2.0)
 05 - R/W             GND
 06 - EN              Pin9 (P2.1)
 07 - DB0             GND
 08 - DB1             GND
 09 - DB2             GND
 10 - DB3             GND
 11 - DB4             Pin10 (P2.2)
 12 - DB5             Pin11 (P2.3)
 13 - DB6             Pin12 (P2.4)
 14 - DB7             Pin13 (P2.5)
 15 - BL+             +5V
 16 - BL-             GND
 ===========================================

==============================================
RESISTOR                   Connect to
---------------------------------------------          
R1                            GND
R1                            push_1(1) 
R2                            GND
R2                            push_2(1)
R3                            GND
R3                            push_3(1)
R4                            GND
R4                            push_4(1)
================================================
================================================
PUSH BUTTON                  Connect to
------------------------------------------------   
PushButton(pullup)-push_1(1)        P1.0
PushButton(pullup)-push_2 (1)       P1.1
PushButton(pullup)-push_3 (1)       p1.4
PushButton(pullup)-push_4 (1)       p1.5
PushButton(pullup)-push_1 (2)       vcc
PushButton(pullup)-push_2 (2)       vcc
PushButton(pullup)-push_3 (2)       vcc
PushButton(pullup)-push_4  (2)      vcc
================================================
 */
#include <LiquidCrystal.h>
LiquidCrystal lcd(P2_0, P2_1, P2_2, P2_3, P2_4, P2_5);
volatile int flag1 = HIGH;//flag counter for stop button
volatile int flag2 = HIGH;// flag counter for vote 
volatile int count[4] = {0,0,0,0};
int stop_button =  5;//p1.3
int party1_button = 7;//p1.5
int party2_button = 2;//p1.0
int party3_button = 6;//p1.4
int temp = 0;
volatile int index;
String party[3]={"party1" ,"party2","party3"};
int i=0;
int j=0,q;
char s[2];
int n=0;
volatile int c=0;
String result_f="party ";
void setup()
{  lcd.begin(16,2);
//All buttons acting pullup
  pinMode(stop_button, INPUT_PULLUP);
  pinMode(party1_button, INPUT_PULLUP);
  pinMode(party2_button, INPUT_PULLUP);
  pinMode(party3_button, INPUT_PULLUP);
  //all button interrupt serivce routines initialsed on falling edges 
attachInterrupt(stop_button, stop1, FALLING);
attachInterrupt(party1_button, poll_1, FALLING);
attachInterrupt(party2_button, poll_2, FALLING);
attachInterrupt(party3_button, poll_3, FALLING);
}
//the function itoi converts the values of integer to display on the lcd 
void itoi(int n, char s[])
{
  s[2]=' ';
  do{
    s[i++] = n%10 + '0';
  }
  while((n=n/10)>0);
  char c;
  for(q=0,j=i-1;q<j;q++,j--)
  {
    c= s[q];
    s[q]=s[j];
    s[j]=c;
  }
}
//loop function iterrates itself throughout the code 
void loop()
{
lcd.clear();
lcd.print("Welcome Voter");
delay(1000);
lcd.clear();
lcd.print("Cast your vote");
delay(1000);
lcd.clear();
//the condition for new voter 
  while((flag1==HIGH)&&(flag2==HIGH))
 { lcd.print("Waiting....");
   delay(200);
  lcd.clear(); 
 }
 //when the stop button is pressed
 if(flag1==LOW)
 result();
 //when the voter has casted vote 
 else if((flag1==HIGH)&&(flag2==LOW))
 { //switch case which tells the voter which party he has opted for
   switch(c)
 {
  case 1:
lcd.print("Thank you!");
delay(2000);
lcd.clear();
lcd.print("Voted for party1");
delay(5000);
lcd.clear();
break;
case 2:
/*s[2]=' ';
itoi(count[1],s);
lcd.print(s);
delay(2000);
lcd.clear();*/
lcd.print("Thank you!");
delay(1000);
lcd.clear();
lcd.print("Voted for party2");
delay(5000);
lcd.clear();
break;
case 3:
lcd.print("Thank you!");
delay(1000);
lcd.clear();
lcd.print("Voted for party3");
delay(5000);
lcd.clear();
break;
case 4:
lcd.print("Thank you!");
delay(1000);
lcd.clear();
lcd.print("Voted for party4");
delay(5000);
lcd.clear();
break;
   case 0:
   lcd.print("No Votes");
delay(1000);
lcd.clear();
 }
 flag2=HIGH;
  }
 } 
 //follwing fuctions of poll_x type save the response for x party and turn of a flag indicting the vote has been casted 
void poll_1()
{  count[0]=count[0]+1;//recording response
  flag2= LOW;//flag
c=1;}
  
 void poll_2()
{  count[1]=count[1]+1;
  flag2= LOW;
c=2;}
  void poll_3()
{  count[2]=count[2]+1;
  flag2= LOW;
c=3;} 
void poll_4()
{  count[3]=count[3]+1;
  flag2= LOW;
c=4;}
//the stop function linked with stop button isr
  void stop1()
  {flag1= LOW;}
  //result function called when loop function encounters that stop was pressed
  void result()
{  lcd.clear();
   lcd.print("Results:");
   delay(500);
  lcd.clear(); 
  //the calculation below finds the largest number ie winner
temp=count[0];
 index=0;
 for(i=1;i<3;i++)
 {
   if(count[i]>temp)
   {temp= count[i];
    index=i;}
 }
 index=index+1;
 //display of results

 lcd.print("*Winner*");
delay(3000);
lcd.clear();
s[2]=' ';
itoi(index,s);
result_f = result_f + s;
lcd.print(result_f);
delay(10000);
lcd.clear();
flag1=HIGH;
for(i=0;i<3;i++)
count[i] = 0;
s[2]=' ';
result_f="party";
}