int led[] = {2, 3, 4, 5, 6, 7};
int del = 50;
void setup() {
  // put your setup code here, to run once:
for (int i = 0; i < 6; i++){
  pinMode(led[i], OUTPUT);
}
pinMode(8, INPUT);
pinMode(9, INPUT);
}


void loop() {
  // put your main code here, to run repeatedly:

if(digitalRead(9) == LOW){

  for (int i=0; i<6; i++){
      digitalWrite(led[i], HIGH);
      delay(del);
  }
  for (int i=0; i<6; i++){
    digitalWrite(led[i],LOW);
    delay(del);
  }
} else {
  for (int i=5; i>=0; i--){
      digitalWrite(led[i], HIGH);
      delay(del);
  }
  for (int i=5; i>=0; i--){
    digitalWrite(led[i],LOW);
    delay(del);
  }
}
}