int ledA = 0;
int ledB = 1;
int ledC = 2;
int ledD = 3;
int ledE = 4;

void setup() {
pinMode ( ledA, OUTPUT);
pinMode ( ledB, OUTPUT);
pinMode ( ledC, OUTPUT);
pinMode ( ledD, OUTPUT);
pinMode ( ledE, OUTPUT);

}

void loop() {
digitalWrite (ledD, HIGH);
delay (500);
digitalWrite (ledC, HIGH);
delay (500);
digitalWrite (ledB, HIGH);
delay (500);
digitalWrite (ledA, HIGH);
delay (500);
digitalWrite (ledE, HIGH);
delay (500);
digitalWrite (ledD, LOW);
digitalWrite (ledC, LOW);
digitalWrite (ledB, LOW);
digitalWrite (ledA, LOW);
digitalWrite (ledE, LOW);
delay (500);
digitalWrite (ledD, HIGH);
digitalWrite (ledC, HIGH);
digitalWrite (ledB, HIGH);
digitalWrite (ledA, HIGH);
digitalWrite (ledE, HIGH);
delay (500);
digitalWrite (ledD, LOW);
digitalWrite (ledC, LOW);
digitalWrite (ledB, LOW);
digitalWrite (ledA, LOW);
digitalWrite (ledE, LOW);
delay (500);
digitalWrite (ledD, HIGH);
digitalWrite (ledC, HIGH);
digitalWrite (ledB, HIGH);
digitalWrite (ledA, HIGH);
digitalWrite (ledE, HIGH);
delay (500);
digitalWrite (ledD, LOW);
digitalWrite (ledC, LOW);
digitalWrite (ledB, LOW);
digitalWrite (ledA, LOW);
digitalWrite (ledE, LOW);
delay (500);
}