// variables
int RED = 18;
int YELL = 4;
int GREEN = 15;
int RED1 = 33;
int YELL1 = 25;
int GREEN1 = 26;
int DELAY_GREEN = 2000;

// basic functions
void setup()
{
  pinMode(RED, OUTPUT);
  pinMode(YELL, OUTPUT);
  pinMode(GREEN, OUTPUT);
  pinMode(RED1, OUTPUT);
  pinMode(YELL1, OUTPUT);
  pinMode(GREEN1, OUTPUT);
}
void loop()
{
 digitalWrite(RED, HIGH);
 digitalWrite(YELL, LOW);
 digitalWrite(GREEN, LOW);
 digitalWrite(RED1, LOW);
 digitalWrite(YELL1, LOW);
 digitalWrite(GREEN1, HIGH);
 delay(DELAY_GREEN);
 digitalWrite(RED, HIGH);
 digitalWrite(YELL, HIGH);
 digitalWrite(GREEN, LOW);
 digitalWrite(RED1, LOW);
 digitalWrite(YELL1, HIGH);
 digitalWrite(GREEN1, HIGH);
 delay(DELAY_GREEN);
 digitalWrite(RED, LOW);
 digitalWrite(YELL, LOW);
 digitalWrite(GREEN, HIGH);
 digitalWrite(RED1, HIGH);
 digitalWrite(YELL1, LOW);
 digitalWrite(GREEN1, LOW);
 delay(DELAY_GREEN);
 digitalWrite(RED, LOW);
 digitalWrite(YELL, HIGH);
 digitalWrite(GREEN, HIGH);
 digitalWrite(RED1, HIGH);
 digitalWrite(YELL1, HIGH);
 digitalWrite(GREEN1, LOW);
 delay(DELAY_GREEN);
}