#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x27,16,2);
#define BTN1 4
#define BTN2 3
#define BTN3 2

float curensy = 0.0;
float result = 0.0;
int choice = 0;

const float USD = 41.38;
const float EUR = 47;
const float PLN = 11;

void setup() {
  lcd.init();
  lcd.clear();        
  lcd.backlight();

  pinMode(BTN1, INPUT_PULLUP);
  pinMode(BTN2, INPUT_PULLUP);
  pinMode(BTN3, INPUT_PULLUP);
}

void loop() {
  if(digitalRead(BTN1)==LOW){
      delay(10); 
      curensy = curensy + 1.1;
      lcd.setCursor(0,0);
      lcd.print(String(curensy) + " UAH");
    }
    
    if(digitalRead(BTN2)==LOW){
    delay(200); 
    choice = choice + 1; 
    if(choice == 1) {
      lcd.setCursor(0,1);
      result = curensy / USD;
      lcd.print("-> USD");
    }

    if(choice == 2) {
      lcd.setCursor(0,1);
      lcd.print("-> EUR");
      result = curensy / EUR;
    }

    if(choice == 3) {
      lcd.setCursor(0,1);
      lcd.print( "-> PLN");
      result = curensy / PLN;
    }

    if(choice > 3) {
      lcd.setCursor(0,1);
      choice = 0;
    }
  }

  if(digitalRead(BTN3)==LOW){
    lcd.clear();
    lcd.setCursor(0,0);
    lcd.print("Result: ");
    
    lcd.setCursor(0,1);
    lcd.print(result);
  }

}