// Define LED pins
const int redPin = 13;
const int yellowPin = 12;
const int greenPin = 11;

// Timing constants (in milliseconds)
const int redDuration = 5000;    // 5 seconds
const int yellowDuration = 2000; // 2 seconds
const int greenDuration = 5000;  // 5 seconds

void setup() {
  // Initialize LED pins as output
  pinMode(redPin, OUTPUT);
  pinMode(yellowPin, OUTPUT);
  pinMode(greenPin, OUTPUT);
}

void loop() {
  // Turn on red light
  digitalWrite(redPin, HIGH);
  delay(redDuration);
  
  // Turn off red light and turn on green light
  digitalWrite(redPin, LOW);
  digitalWrite(greenPin, HIGH);
  delay(greenDuration);
  
  // Turn off green light and turn on yellow light
  digitalWrite(greenPin, LOW);
  digitalWrite(yellowPin, HIGH);
  delay(yellowDuration);
  
  // Turn off yellow light
  digitalWrite(yellowPin, LOW);
}