#include <LiquidCrystal.h>

LiquidCrystal lcd(12, 11, 10, 9, 8, 7);
int r = 2;
int l = 3;
int gp = 0;
int lp = 0;
void setup() {
  Serial.begin(115200);
  lcd.begin(16, 2);
  pinMode(r, INPUT);
  pinMode(l, INPUT);
  lcd.clear();
  lcd.cursor();
  lcd.setCursor(gp, lp);
}

void loop() {
  while (digitalRead(l) != 0 && digitalRead(r) != 0);
  if (digitalRead(l) == 1 and gp != 0){
    gp -= 1;
    Serial.println(-1);
  }
  else if (digitalRead(r) == 1 and gp != 16){
    gp += 1;
    Serial.println(1);
  }
  while (digitalRead(l) != 1 && digitalRead(r) != 1);
  lcd.setCursor(gp, lp);
}