int RED_LED = 12;
int BLUE_LED = 13;
int YELLOW_LED = 11;

void setup() {
  // put your setup code here, to run once:
pinMode(RED_LED, OUTPUT);
pinMode(BLUE_LED, OUTPUT);
pinMode(YELLOW_LED, OUTPUT);
}

void loop() {
  // put your main code here, to run repeatedly:
digitalWrite(RED_LED, HIGH);
delay(400);
digitalWrite(BLUE_LED, HIGH);
delay(400);
digitalWrite(YELLOW_LED, HIGH);
delay(400);
if(digitalRead(BLUE_LED) == HIGH and digitalRead(YELLOW_LED) == HIGH and digitalRead(RED_LED) == HIGH)
{
digitalWrite(BLUE_LED, LOW);
digitalWrite(RED_LED, LOW);
digitalWrite(YELLOW_LED, LOW);
}
delay(400);
}