int ledPins[] = {2,3,4,5,6,7,8,9}; void setup() { for(int i = 0; i < 8; i++) { pinMode(ledPins[i],OUTPUT); } } void loop() { for(int i = 0; i < 8; i++) { digitalWrite(i, HIGH); // Turn on the LED delay(1000); // Wait for one second digitalWrite(i, LOW); // Turn off the LED delay(1000); //Wait one second } }