どっちを押すと光る？-プログラム

#include <LiquidCrystal.h>

const int leftbutton = 11;
const int rightbutton = 12;

const int ledpin = 10;

int rightbuttonState=0;
int leftbuttonState=0;
int randNumber =0;


void setup(){
  pinMode(ledpin,OUTPUT);
  pinMode(rightbutton,INPUT);
  pinMode(leftbutton,INPUT);
  Serial.begin(9600) ;
  randomSeed(analogRead(0));
  randNumber = random(3);
}

void loop(){
  rightbuttonState = digitalRead(rightbutton);
  leftbuttonState = digitalRead(leftbutton);
  if(randNumber == 0){
    if(rightbuttonState == HIGH &&leftbuttonState == LOW){
      digitalWrite(ledpin,HIGH);
    }else{
      digitalWrite(ledpin,LOW);
    }
  }else if(randNumber == 1) {
     if(rightbuttonState == LOW &&leftbuttonState == HIGH){
      digitalWrite(ledpin,HIGH);
    }else{
      digitalWrite(ledpin,LOW);
    }
  }else if(randNumber == 2) {
     if(rightbuttonState == HIGH &&leftbuttonState == HIGH){
      digitalWrite(ledpin,HIGH);
    }else{
      digitalWrite(ledpin,LOW);
    }
  }
  delay(100);
}