int ledpins[]={2,3,4,5,6,7,8,9};
void setup() {
  // put your setup code here, to run once:
int index;
for(index=0;index<=7;index++){
pinMode(ledpins[index], OUTPUT);
}
}

void loop() {
  // put your main code here, to run repeatedly:
  int index;
  for(index=0;index<=7;index++){
  digitalWrite(ledpins[index], HIGH);
  delay(1000);
  }
for(index=0;index<=7;index++)
{
  digitalWrite(ledpins[index], LOW);
  delay(1000);
}
}