#include <Arduino.h>  // Explicitly include standard Arduino header

// Pin definitions for Traffic Light 1
static const int RED1 = 13;    // Red light for Traffic Light 1
static const int YELLOW1 = 12; // Yellow light for Traffic Light 1
static const int GREEN1 = 11;  // Green light for Traffic Light 1

// Pin definitions for Traffic Light 2
static const int RED2 = 10;    // Red light for Traffic Light 2
static const int YELLOW2 = 9;  // Yellow light for Traffic Light 2
static const int GREEN2 = 8;   // Green light for Traffic Light 2

// Traffic light delay durations (in milliseconds)
static const unsigned int GREEN_DELAY = 5000U;  // Green light duration: 5 seconds
static const unsigned int YELLOW_DELAY = 2000U; // Yellow light duration: 2 seconds

void setup(void) 
{
    // Set all traffic light pins as outputs
    pinMode(RED1, OUTPUT);
    pinMode(YELLOW1, OUTPUT);
    pinMode(GREEN1, OUTPUT);
    
    pinMode(RED2, OUTPUT);
    pinMode(YELLOW2, OUTPUT);
    pinMode(GREEN2, OUTPUT);
}

void loop(void) 
{
    /* Step 1: Green for Traffic 1, Red for Traffic 2 */
    digitalWrite(GREEN1, HIGH); // Turn on green light for Traffic Light 1
    digitalWrite(RED2, HIGH);   // Turn on red light for Traffic Light 2
    delay(GREEN_DELAY);         // Wait for green light duration
    
    /* Step 2: Yellow for Traffic 1 */
    digitalWrite(GREEN1, LOW);  // Turn off green light for Traffic Light 1
    digitalWrite(YELLOW1, HIGH); // Turn on yellow light for Traffic Light 1
    delay(YELLOW_DELAY);        // Wait for yellow light duration
    
    /* Step 3: Red for Traffic 1, Green for Traffic 2 */
    digitalWrite(YELLOW1, LOW); // Turn off yellow light for Traffic Light 1
    digitalWrite(RED1, HIGH);   // Turn on red light for Traffic Light 1
    digitalWrite(RED2, LOW);    // Turn off red light for Traffic Light 2
    digitalWrite(GREEN2, HIGH); // Turn on green light for Traffic Light 2
    delay(GREEN_DELAY);         // Wait for green light duration
    
    /* Step 4: Yellow for Traffic 2 */
    digitalWrite(GREEN2, LOW);  // Turn off green light for Traffic Light 2
    digitalWrite(YELLOW2, HIGH); // Turn on yellow light for Traffic Light 2
    delay(YELLOW_DELAY);        // Wait for yellow light duration
    
    /* Step 5: Reset to Red for Traffic 2, Green for Traffic 1 */
    digitalWrite(YELLOW2, LOW); // Turn off yellow light for Traffic Light 2
    digitalWrite(RED2, HIGH);   // Turn on red light for Traffic Light 2
    digitalWrite(RED1, LOW);    // Turn off red light for Traffic Light 1
}