int led1 = 8;
int led2 = 13;
int led3 = 11;
int led4 = 9;
int led5 = 10;

void setup() {
pinMode ( led1,OUTPUT);
pinMode ( led2,OUTPUT);
pinMode ( led3, OUTPUT);
pinMode ( led4, OUTPUT);
pinMode ( led5, OUTPUT);
}

void loop() {
digitalWrite ( led1, HIGH);
delay(100);
digitalWrite ( led1, LOW);
delay(100);
digitalWrite ( led2, HIGH);
delay(100);
digitalWrite ( led2, LOW);
delay(100);
digitalWrite ( led3, HIGH);
delay(100);
digitalWrite ( led3, LOW);
delay(100);
digitalWrite ( led4, HIGH);
delay(100);
digitalWrite ( led4, LOW);
delay(100);
digitalWrite ( led5, HIGH);
delay(100);
digitalWrite ( led5, LOW);
delay(100);
digitalWrite ( led4, HIGH);
delay(100);
digitalWrite ( led4, LOW);
delay(100);
digitalWrite ( led3, HIGH);
delay(100);
digitalWrite ( led3, LOW);
delay(100);
digitalWrite ( led2, HIGH);
delay(100);
digitalWrite ( led2, LOW);
delay(100);
digitalWrite ( led1, HIGH);
delay(100);
digitalWrite ( led1, LOW);
delay(100);
}