void setup() {
pinMode(5, OUTPUT);
pinMode(6, OUTPUT);
pinMode(7, OUTPUT);
pinMode(8, OUTPUT);
pinMode(9, OUTPUT);
pinMode(10, OUTPUT);
pinMode(11, OUTPUT);
pinMode(12, OUTPUT);
}

void loop() {
digitalWrite(12, 1);
delay(1000);
digitalWrite(12, 0);
digitalWrite(11, 1);
delay(1000);

digitalWrite(11, 0);
digitalWrite(10, 1);
delay(1000);

digitalWrite(10, 0);
digitalWrite(9, 1);
delay(1000);

digitalWrite(9, 0);
digitalWrite(8, 1);
delay(1000);

digitalWrite(8, 0);
digitalWrite(7, 1);
delay(1000);

digitalWrite(7, 0);
digitalWrite(6, 1);
delay(1000);

digitalWrite(6,0);
digitalWrite(5, 1);
delay(1000);

digitalWrite(5, 0);
}