#include <LiquidCrystal.h>
LiquidCrystal lcd(18, 5, 17, 16, 4, 0);
int count1 = 0;
int count2 = 0;
void setup() {
lcd.begin(16, 2);
Serial.begin(115200);
}
  void loop(){

  
}
void serialEvent()
{
char ch;
 while (Serial.available()) {
 char ch = Serial.read();
 Serial.print(ch);
 
 
 if(ch == '1'){
  count1++;
  lcd.setCursor(0,0);
  lcd.print("count 1: ");
  lcd.print(count1);
 }
  else if(ch == '2'){
  count2++;
  lcd.setCursor(0,1);
  lcd.print("count 2: ");
  lcd.print(count2);
 }
 else if(ch == '3'){
  count1--;
  lcd.setCursor(0,0);
  lcd.print("count 1: ");
  lcd.print(count1);
 }
  else if(ch == '4'){
  count2--;
  lcd.setCursor(0,1);
  lcd.print("count 2: ");
  lcd.print(count2);
 }
 
 }
}