void setup() {
  // put your setup code here, to run once:
pinMode(2, OUTPUT);
pinMode(3, OUTPUT);
pinMode(4, OUTPUT);
pinMode(5, OUTPUT);
pinMode(6, OUTPUT);
pinMode(7, OUTPUT);
pinMode(8, OUTPUT);
pinMode(9, OUTPUT);
pinMode(10, OUTPUT);
pinMode(11, OUTPUT);
pinMode(12, OUTPUT);
pinMode(13, OUTPUT);

}
void loop() {
  // put your main code here, to run repeatedly:
int led;
for(led=2;led>14;led++) {
  if(led=2) {
    digitalWrite(led,1);
    delay(100);
    digitalWrite(led+1,1);
    delay(100);
  }
  else {
    digitalWrite(led,0);
    delay(100);
    digitalWrite(led-1,0);
    delay(100);
  }
}
}