// variables

int Green = 2;
int Yellow = 3;
int Red = 4;
int Delay_Green = 3000;
int Delay_Yellow = 2000;
int Delay_Red = 3000;


void setup() {
  // put your setup code here, to run once:
  pinMode(Green, OUTPUT);
  pinMode(Yellow, OUTPUT);
  pinMode(Red, OUTPUT);
}



void loop() {
  // put your main code here, to run repeatedly:
  green_light();
  delay(Delay_Green);
  yellow_light();
  delay(Delay_Yellow);
  red_light();
  delay(Delay_Red);
  
}

void green_light(){
  digitalWrite(Green, HIGH);
  digitalWrite(Yellow, LOW);
  digitalWrite(Red, LOW);
}

void yellow_light(){
  digitalWrite(Green, LOW);
  digitalWrite(Yellow, HIGH);
  digitalWrite(Red, LOW);
}

void red_light(){
  digitalWrite(Green, LOW);
  digitalWrite(Yellow, LOW);
  digitalWrite(Red, HIGH);
}