#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x27,16,2);
#define in A0
#define out A1 
int count=0; 
void IN()
{
  count++; 
  lcd.print("Students In");
  lcd.setCursor(0,1);
  lcd.print("Class Room:");
  lcd.setCursor(12,1);
  lcd.print(count);
  delay(500);
}
void OUT()
{
  count--;
  lcd.print("Students In");
  lcd.setCursor(0,1);
  lcd.print("Class Room:");
  lcd.setCursor(12,1);
  lcd.print(count);
  delay(500);
}
void setup()
{
  lcd.init();
  lcd.backlight();  
  lcd.print(" EC_STD_Counter");
  delay(3000);
  pinMode(in, INPUT);
  pinMode(out, INPUT);
  lcd.clear();
  lcd.print("Students In");
  lcd.setCursor(0,1);
  lcd.print("Class Room:");
  lcd.setCursor(12,1);
  lcd.print(count);
}
void loop()
{
  if(digitalRead(in))
  IN();
  if(digitalRead(out))
  OUT();
}