traffic light

int green_time = 10; // seconds to keep green light
float yellow_time = 0.5; // seconds to delay flash time
int flash_times = 5; // times to flash green light

int red1 = 11;
int yellow1 = 12;
int green1 = 13;

int red2 = 3;
int yellow2 = 4;
int green2 = 5;

// the setup routine runs once when you press reset:
void setup() {                
  // initialize the digital pin as an output.
  pinMode(red1, OUTPUT);   
  pinMode(green1, OUTPUT);     
  pinMode(yellow1, OUTPUT);   
  
  pinMode(red2, OUTPUT);   
  pinMode(green2, OUTPUT);     
  pinMode(yellow2, OUTPUT); 
  
}

// the loop routine runs over and over again forever:
void loop() {
  //at first, turn on red1 and green2
  digitalWrite(green2, HIGH);
  digitalWrite(red1, HIGH);
  delay(1000 * green_time);
  digitalWrite(green2, LOW);
  
  //flash yellow2
  for(int i = 0; i < flash_times; i++) {
    digitalWrite(yellow2, HIGH);
    delay(1000 * yellow_time);
    digitalWrite(yellow2, LOW);
    delay(1000 * yellow_time);
  }
  
  //turn off yellow2, red1 and turn on red2, green1
  digitalWrite(red1, LOW);
  digitalWrite(red2, HIGH);
  digitalWrite(green1, HIGH);
  delay(1000 * green_time);
  digitalWrite(green1, LOW);
  
  //flash yellow1
  for(int i = 0; i < flash_times; i++) {
    digitalWrite(yellow1, HIGH);
    delay(1000 * yellow_time);
    digitalWrite(yellow1, LOW);
    delay(1000 * yellow_time);
  }

  //turn off red2 and red1, green2 will be turned on on next loop
  digitalWrite(red2, LOW);
}