#include <LiquidCrystal_I2C.h>

#define I2C_ADDR    0x27
#define LCD_COLUMNS 20
#define LCD_LINES   4

LiquidCrystal_I2C lcd(I2C_ADDR, LCD_COLUMNS, LCD_LINES);

int v=0;
int h=0;
int r=0;
int r_OLD=24;
int c=0;
int c_OLD=24;

void setup() 
{
  lcd.init();
  lcd.backlight(); 
  pinMode(A0, INPUT);
  pinMode(A1, INPUT);
  pinMode(2, INPUT);
}

void loop() 
{
  v=analogRead(A1);
  h=analogRead(A0);
  if(v>900)
  {
    r=r-1;
    if(r<0)
    {
      r=3;
    }
    while(v!=512)
    {
      v=analogRead(A1);
      delay(10);
    }
  }
  if (v<100)
  {
    r=r+1;
    if(r>3)
    {
      r=0;
    }
     while(v!=512)
    {
      v=analogRead(A1);
      delay(10);
    }
  }
  if(h<100)
  {
    c=c+1;
    if(c>19)
    {
      c=0;
    }
    while(h!=512)
    {
      h=analogRead(A0);
      delay(10);
    }
  }
  if(h>900)
  {
        c=c-1;
      if(c<0)
      {
          c=19;
      }
      while(h!=512)
      {
      h=analogRead(A0);
      delay(10);
      }
  }
   if(c != c_OLD || r != r_OLD)
   {
    lcd.clear();
    lcd.setCursor(c,r);
    lcd.print("*");
   }
    
  

  r_OLD=r;
  c_OLD=c;
}