// C++ code
//
void setup() {
    
    pinMode(2,OUTPUT);
    pinMode(4,OUTPUT);
    pinMode(5,OUTPUT);
}

void loop() {
    digitalWrite(2, HIGH);
    delay(1000);
    digitalWrite(2, LOW);

    digitalWrite(4, HIGH);
    delay(1000);
    digitalWrite(4, LOW);

    digitalWrite(5, HIGH);
    delay(1000);
    digitalWrite(5, LOW);
}