const int greenNorthSouthPin = 23;
const int yellowNorthSouthPin = 22;
const int redNorthSouthPin = 21;
const int greenEastWestPin = 19;
const int yellowEastWestPin = 18;
const int redEastWestPin = 17;
const int greenTime = 5000; 
const int yellowTime = 2000; 
const int redTime = 5000; 

void setup() {
  pinMode(greenNorthSouthPin, OUTPUT);
  pinMode(yellowNorthSouthPin, OUTPUT);
  pinMode(redNorthSouthPin, OUTPUT);
  pinMode(greenEastWestPin, OUTPUT);
  pinMode(yellowEastWestPin, OUTPUT);
  pinMode(redEastWestPin, OUTPUT);
}

void loop() {
  digitalWrite(greenNorthSouthPin, HIGH);
  digitalWrite(yellowEastWestPin, LOW);
  digitalWrite(redEastWestPin, HIGH);
  digitalWrite(greenEastWestPin, LOW);
  digitalWrite(redNorthSouthPin, LOW);
  digitalWrite(yellowNorthSouthPin, LOW);
  delay(greenTime);
  
  digitalWrite(greenNorthSouthPin, LOW);
  digitalWrite(yellowNorthSouthPin, HIGH);
  digitalWrite(redNorthSouthPin, LOW);
  digitalWrite(yellowEastWestPin, HIGH);
  digitalWrite(redEastWestPin, LOW);
  digitalWrite(greenEastWestPin, LOW);
  delay(yellowTime);
  
  digitalWrite(yellowNorthSouthPin, LOW);
  digitalWrite(redNorthSouthPin, HIGH);
  digitalWrite(greenNorthSouthPin, LOW);
  digitalWrite(greenEastWestPin, HIGH);
  digitalWrite(redEastWestPin, LOW);
  digitalWrite(yellowEastWestPin, LOW);
  delay(redTime);
  
  digitalWrite(greenNorthSouthPin, LOW);
  digitalWrite(yellowNorthSouthPin, HIGH);
  digitalWrite(redNorthSouthPin, LOW);
  digitalWrite(yellowEastWestPin, HIGH);
  digitalWrite(redEastWestPin, LOW);
  digitalWrite(greenEastWestPin, LOW);
  delay(yellowTime);
}