#include <Wire.h>
#include <LiquidCrystal_I2C.h>

LiquidCrystal_I2C lcd(0x27, 16, 2);

int cambien = 10;
int dem = 0;
int pre = LOW;
int resetButtonPin = 3;

void setup() {
  pinMode(cambien, INPUT);
  pinMode(resetButtonPin, INPUT_PULLUP);

  lcd.init(); 
  lcd.backlight(); 
  lcd.setCursor(0, 0);
  lcd.print("Counter: ");
}

void loop() {
  int gtcb = digitalRead(cambien);
  if(gtcb == LOW && pre == HIGH) {
    dem = dem + 1;
    delay(100);
  }

  pre = gtcb;
  lcd.setCursor(0,0);
  lcd.print("So luong: ");
  lcd.setCursor(10,0);
  lcd.print(dem);

  if (digitalRead(resetButtonPin) == LOW) { 
    dem = 0;
    lcd.clear();
    delay(100);
    lcd.setCursor(10, 0);
    lcd.print(dem);
  }
}