int ledRed = 13;
int ledYell = 12;
int ledGreen = 11;
int switchpin = 10;
bool ledState = false;

void setup() {
  pinMode(ledRed, OUTPUT);
  pinMode(ledYell, OUTPUT);
  pinMode(ledGreen, OUTPUT);
  pinMode(switchpin, INPUT_PULLUP);
}

void loop() {
  int switchstate = digitalRead(switchpin);
  if (switchstate == LOW) {
    ledState = !ledState;
    delay(1000);
    
    while (digitalRead(switchpin) == LOW) {
      
      if (ledState) {
        digitalWrite(ledRed, HIGH);
        delay(500);
        digitalWrite(ledRed, LOW);
        digitalWrite(ledYell, HIGH);
        delay(500);
        digitalWrite(ledYell, LOW);
        digitalWrite(ledGreen, HIGH);
        delay(500);
        digitalWrite(ledGreen, LOW);
        delay(500);
        digitalWrite(ledGreen, HIGH);
        delay(500);
        digitalWrite(ledYell, HIGH);
        digitalWrite(ledGreen, LOW);
        delay(500);
        digitalWrite(ledRed, HIGH);
        digitalWrite(ledYell, LOW);
        delay(500);
        digitalWrite(ledRed, LOW);
        delay(500);
      } else{
        digitalWrite(ledRed, LOW);
        digitalWrite(ledYell, LOW);
        digitalWrite(ledGreen, LOW);
      }
    }
  }
}