/*
  Blink

  Turns an LED on for one second, then off for one second, repeatedly.

  Most Arduinos have an on-board LED you can control. On the UNO, MEGA and ZERO
  it is attached to digital pin 13, on MKR1000 on pin 6. LED_BUILTIN is set to
  the correct LED pin independent of which board is used.
  If you want to know what pin the on-board LED is connected to on your Arduino
  model, check the Technical Specs of your board at:
  https://www.arduino.cc/en/Main/Products

  modified 8 May 2014
  by Scott Fitzgerald
  modified 2 Sep 2016
  by Arturo Guadalupi
  modified 8 Sep 2016
  by Colby Newman

  This example code is in the public domain.

  http://www.arduino.cc/en/Tutorial/Blink
*/

// the setup function runs once when you press reset or power the board
void setup() {
  
  pinMode(1, OUTPUT);     //红灯接1  
  pinMode(2, OUTPUT);     //黄灯接2
  pinMode(3, OUTPUT);     //绿灯接3
}


void loop() {
  digitalWrite(1, HIGH);     //红灯亮
  digitalWrite(2,LOW);     //黄灯不亮        
  digitalWrite(3,LOW);     //绿灯不亮
  delay(5000);     //红灯亮的时间是5秒
  
  digitalWrite(1, LOW);     //红灯不亮
  digitalWrite(3, LOW);     //绿灯不亮
  for(int i = 0;i<3;i++){     //黄灯闪烁3次持续3秒
    digitalWrite(2,HIGH);     //黄灯亮
    delay(500);     //黄灯亮0.5秒
    digitalWrite(2, LOW);     //黄灯灭
    delay(500);     //黄灯灭0.5秒
  }

  digitalWrite(3, HIGH);     //绿灯亮
  digitalWrite(2,LOW);     //黄灯不亮
  digitalWrite(1,LOW);     //红灯不亮
  delay(2000);     //绿灯常亮2秒
  for(int j = 0;j<3;j++){     //绿灯闪烁3次持续3秒
    digitalWrite(3, HIGH);     //绿灯亮
    delay(500);     //绿灯亮0.5秒
    digitalWrite(3, LOW);     //绿灯灭
    delay(500);     //绿灯灭0.5秒
  }
}