#include <LiquidCrystal.h>

LiquidCrystal monitor(2,3,4,5,6,7);//(RS,E,DB4,DB5,DB6,DB7)

byte linha=0;
byte coluna=0;

void setup()
{
   monitor.begin(20,4);//(colunas, linhas) do LCD  
}
void loop()
{
   monitor.setCursor(coluna,0);
   monitor.print("*");
   if(analogRead(A1)==0 and coluna<19)
   {
      coluna++;
      delay(100);
      monitor.clear();
   }
   if(analogRead(A1)==1023 and coluna>0)
   {
     coluna--;
     delay(100);
     monitor.clear();
   }
}