#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x27, 16, 2);
const int b1 = 4, b2 = 2; int up, down, cnt = 0;
void setup() {
  Serial.begin(115200);
  pinMode(b1, INPUT_PULLUP);
  pinMode(b2, INPUT_PULLUP);
  lcd.init(); lcd.backlight(); lcd.setCursor(3, 0); lcd.print("HELLO AIB");
  delay(500);
  lcd.clear();
}
void loop() {
  up = !digitalRead(b1); down = !digitalRead(b2);
  Serial.print(up); Serial.print(", "); Serial.print(down); Serial.print(", ");
  switch (up) {
    case 1:
      cnt++;
      break;
  }
  switch (down) {
    case 1:
      cnt--;
      break;
  }
  delay(50);
  Serial.print("counter = "); Serial.println(cnt);
  lcd.setCursor(4, 0);
  lcd.print("Counter:");
  lcd.setCursor(4, 1);
  lcd.print(cnt);
  if (cnt <= 9) {
    lcd.setCursor(5, 1);
    lcd.print("           ");
  }
  else if (cnt <= 99) {
    lcd.setCursor(6, 1);
    lcd.print("          ");
  }
  else if (cnt <= 999) {
    lcd.setCursor(7, 1);
    lcd.print("         ");
  }

}