// Define the pin numbers for the traffic light LEDs
#define RED_PIN 2
#define YELLOW_PIN 3
#define GREEN_PIN 4

// Define the waiting time for each state in milliseconds
#define RED_TIME 20000
#define GREEN_TIME 20000
#define YELLOW_TIME 5000
#define TRANSISION_TIME 150

// Function to control the traffic light
void trafficLight() {
  // Set the initial state of the traffic light to red
  digitalWrite(RED_PIN, HIGH);
  digitalWrite(YELLOW_PIN, LOW);
  digitalWrite(GREEN_PIN, LOW);
  
  // Infinite loop to continuously cycle through the traffic light states
  while (true) {
    // Delay for the specified time in the current state
    delay(RED_TIME);
    
    // Change the state from red to green
    digitalWrite(RED_PIN, LOW);
    digitalWrite(YELLOW_PIN, LOW);
    // Delay for the specified time in the current state
    delay(TRANSISION_TIME);
    digitalWrite(GREEN_PIN, HIGH);
    
    // Delay for the specified time in the current state
    delay(GREEN_TIME);
    
    // Change the state from green to yellow
    digitalWrite(RED_PIN, LOW);
    digitalWrite(GREEN_PIN, LOW);
        // Delay for the specified time in the current state
    delay(TRANSISION_TIME);
    digitalWrite(YELLOW_PIN, HIGH);
    
    // Delay for the specified time in the current state
    delay(YELLOW_TIME);
  
    // Change the state from yellow to red
    digitalWrite(YELLOW_PIN, LOW);
    digitalWrite(GREEN_PIN, LOW);
    delay(TRANSISION_TIME);
    // Delay for the specified time in the current state
    digitalWrite(RED_PIN, HIGH);
  }
}

void setup() {
  // Set the pin modes for the traffic light LEDs
  pinMode(RED_PIN, OUTPUT);
  pinMode(YELLOW_PIN, OUTPUT);
  pinMode(GREEN_PIN, OUTPUT);
}

void loop() {
  // Call the trafficLight function to start the traffic light program
  trafficLight();
}