int pinLed [] = {0,1,2,3,4,5,6,7};
int i,j;
void nhapnhay()
{
  for (i=0;i<=7;i++)
    digitalWrite(pinLed[i], LOW);
  delay(300);
  for(i=0;i<=7;i++)
    digitalWrite(pinLed[i], HIGH);
  delay(300);
}
void setup()
{
  for(i=0;i<=7;i++)
    pinMode(pinLed[i], OUTPUT);
}
void loop()
{
  nhapnhay();
}