int counter = 1;

//leds
int l1 = 2;
int l2 = 3;
int l3 = 4;

//BUTTON
int buttonL = 5;
int buttonR = 6;

void setup() {
// put your setup code here, to run once:
pinMode(l1,OUTPUT);
pinMode(l2,OUTPUT);
pinMode(l3,OUTPUT);

pinMode(buttonL,INPUT);
digitalWrite(buttonL,HIGH);

pinMode(buttonR,INPUT);
digitalWrite(buttonR,HIGH);

Serial.begin(9600);
}

void loop() {
//Serial.println(counter);
Serial.println(digitalRead(buttonR));
if (digitalRead(buttonL) == 0){
while (digitalRead(buttonL) == 0){}
if (counter - 1 == 0){
counter = 3;
}
else{
counter = counter - 1;
}
}

if (digitalRead(buttonR) == 0){
while (digitalRead(buttonR) == 0){Serial.println(digitalRead(buttonR));}
if (counter + 1 == 4){
counter = 1;
}
else{
counter = counter + 1;
}
}


//lighting leds

if (counter == 1){
digitalWrite(l3,LOW);
digitalWrite(l2,LOW);
digitalWrite(l1,HIGH);
}
if (counter == 2){
digitalWrite(l1,LOW);
digitalWrite(l3,LOW);
digitalWrite(l2,HIGH);
}
if (counter == 3){
digitalWrite(l1,LOW);
digitalWrite(l2,LOW);
digitalWrite(l3,HIGH);
}

}