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

#define BUTTON_A_PIN 2
#define BUTTON_B_PIN 3
#define BUTTON_C_PIN 4

LiquidCrystal_I2C lcd(0x27, 16, 2);

void setup() {
  pinMode(BUTTON_A_PIN, INPUT_PULLUP);
    pinMode(BUTTON_B_PIN, INPUT_PULLUP);
      pinMode(BUTTON_C_PIN, INPUT_PULLUP);

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

          void loop() {
            char input = readInput();

              if (input != 0) {
                  displayInput(input);
                    }
                    }

                    char readInput() {
                      if (digitalRead(BUTTON_A_PIN) == LOW) {
                          return 'A';
                            }
                              else if (digitalRead(BUTTON_B_PIN) == LOW) {
                                  return 'B';
                                    }
                                      else if (digitalRead(BUTTON_C_PIN) == LOW) {
                                          return 'C';
                                            }

                                              return 0;
                                              }

                                              void displayInput(char input) {
                                                lcd.setCursor(0, 0);
                                                  lcd.print("Pressed: ");
                                                    lcd.print(input);
                                                    }