int ledPin1 = 2; //GREEN
int ledPin2 = 3; //BLUE
int ledPin3 = 4; //YELLOW
int ledPin4 = 5; //RED
int buttonPin = 13;
int buttonState = HIGH;

void setup() {
  Serial.begin(9600);

  pinMode(ledPin1, OUTPUT);
  pinMode(ledPin2, OUTPUT);
  pinMode(ledPin3, OUTPUT);
  pinMode(ledPin4, OUTPUT);
  pinMode(buttonPin, INPUT_PULLUP);

}

void loop() {

buttonState = digitalRead(buttonPin);

static int state = 1;


if (buttonState == LOW) {
  switch (state) {
    case 1:
      analogWrite(ledPin1, 150);
      analogWrite(ledPin4, 0);
      state = 2;
      delay(200);
    case 2:
      analogWrite(ledPin2, 150);
      analogWrite(ledPin1, 0);
      state = 3;
      delay(200);
    case 3:
      analogWrite(ledPin3, 150);
      analogWrite(ledPin2, 0);
      state = 4;
      delay(200);
    case 4:
      analogWrite(ledPin4, 150);
      analogWrite(ledPin3, 0);
      state = 1;
      delay(200);

    default: break;
  }
}else {
  analogWrite(ledPin1 , 0);
  analogWrite(ledPin2 , 0);
  analogWrite(ledPin3 , 0);
  analogWrite(ledPin4 , 0);

}


}