int greenPin3 = 2;
int yellowPin3 = 3;
int redPin3 = 4;
int greenPin2 = 5;
int yellowPin2 = 6;
int redPin2 = 7;
int greenPin1 = 8;
int yellowPin1 = 9;
int redPin1 = 10;
void setup() {
  // put your setup code here, to run once:
pinMode (redPin1,OUTPUT);
pinMode (yellowPin1,OUTPUT);
pinMode (greenPin1,OUTPUT);
pinMode (redPin2,OUTPUT);
pinMode (yellowPin2,OUTPUT);
pinMode (greenPin2,OUTPUT);
pinMode (redPin3,OUTPUT);
pinMode (yellowPin3,OUTPUT);
pinMode (greenPin3,OUTPUT);
}

void loop() {
  // put your main code here, to run repeatedly:
digitalWrite (redPin1,LOW);
digitalWrite (yellowPin1,LOW);
digitalWrite (greenPin1,HIGH);
digitalWrite (redPin2,HIGH);
digitalWrite (yellowPin2,LOW);
digitalWrite (greenPin2,LOW);
digitalWrite (redPin3,HIGH);
digitalWrite (yellowPin3,LOW);
digitalWrite (greenPin3,LOW);
delay (3000);
digitalWrite (redPin1,LOW);
digitalWrite (yellowPin1,HIGH);
digitalWrite (greenPin1,LOW);
digitalWrite (redPin2,LOW);
digitalWrite (yellowPin2,HIGH);
digitalWrite (greenPin2,LOW);
digitalWrite (redPin3,HIGH);
digitalWrite (yellowPin3,LOW);
digitalWrite (greenPin3,LOW);
delay (1000);
digitalWrite (redPin1,HIGH);
digitalWrite (yellowPin1,LOW);
digitalWrite (greenPin1,LOW);
digitalWrite (redPin2,LOW);
digitalWrite (yellowPin2,LOW);
digitalWrite (greenPin2,HIGH);
digitalWrite (redPin3,HIGH);
digitalWrite (yellowPin3,LOW);
digitalWrite (greenPin3,LOW);
delay (3000);
digitalWrite (redPin1,HIGH);
digitalWrite (yellowPin1,LOW);
digitalWrite (greenPin1,LOW);
digitalWrite (redPin2,LOW);
digitalWrite (yellowPin2,HIGH);
digitalWrite (greenPin2,LOW);
digitalWrite (redPin3,LOW);
digitalWrite (yellowPin3,HIGH);
digitalWrite (greenPin3,LOW);
delay (1000);
digitalWrite (redPin1,HIGH);
digitalWrite (yellowPin1,LOW);
digitalWrite (greenPin1,LOW);
digitalWrite (redPin2,HIGH);
digitalWrite (yellowPin2,LOW);
digitalWrite (greenPin2,LOW);
digitalWrite (redPin3,LOW);
digitalWrite (yellowPin3,LOW);
digitalWrite (greenPin3,HIGH);
delay (3000);
digitalWrite (redPin1,LOW);
digitalWrite (yellowPin1,HIGH);
digitalWrite (greenPin1,LOW);
digitalWrite (redPin2,HIGH);
digitalWrite (yellowPin2,LOW);
digitalWrite (greenPin2,LOW);
digitalWrite (redPin3,LOW);
digitalWrite (yellowPin3,HIGH);
digitalWrite (greenPin3,LOW);
delay (1000);
}