#include <LiquidCrystal_I2C.h>

LiquidCrystal_I2C lcd(0x27, 16, 2);

const int buttonPin = 12;
const int sessionDuration = 25 * 60 * 1000;
unsigned long int startTime;
unsigned long int stopTime;

void setup() {
  Serial.begin(115200);
  pinMode(buttonPin, INPUT_PULLUP);

  lcd.init();
  lcd.backlight();
}

void loop() {
  int buttonState = digitalRead(buttonPin);


  delay(100);
  lcd.setCursor(0, 0);
  lcd.print(f);
}