void setup() 
{
 pinMode (2, OUTPUT); // use as a output pin for LED 1
 pinMode (3, OUTPUT); // use as a output pin for LED 2
 pinMode (4, OUTPUT); // use as a output pin for LED 3
 pinMode (5, OUTPUT); // use as a output pin for LED 4
 pinMode (6, OUTPUT); // use as a output pin for LED 5
 pinMode (7, OUTPUT); // use as a output pin for LED 6
 pinMode (8, OUTPUT); // use as a output pin for LED 7
 pinMode (9, OUTPUT); // use as a output pin for LED 8
}

void loop() 
{
  digitalWrite (3, HIGH); //LED 1 is ON
  digitalWrite (4, HIGH); //LED 2 is ON
  digitalWrite (5, HIGH); //LED 3 is ON
  digitalWrite (6, HIGH); //LED 4 is ON
  digitalWrite (7, HIGH); //LED 5 is ON
  digitalWrite (8, HIGH); //LED 6 is ON
  digitalWrite (9, HIGH); //LED 7 is ON
  digitalWrite (2, HIGH); //LED 8 is ON
  delay (500); // duration delay
  digitalWrite (3, LOW); //LED 1 is OFF
  digitalWrite (4, LOW); //LED 2 is OFF
  digitalWrite (5, LOW); //LED 3 is OFF
  digitalWrite (6, LOW); //LED 4 is OFF
  digitalWrite (7, LOW); //LED 5 is OFF
  digitalWrite (8, LOW); //LED 6 is OFF
  digitalWrite (9, LOW); //LED 7 is OFF
  digitalWrite (2, LOW); //LED 8 is OFF
  delay (500); // duration delay
  

}