void setup() {
pinMode(2,OUTPUT);
pinMode(3,OUTPUT);
pinMode(4,OUTPUT);
pinMode(5,OUTPUT);
pinMode(6,OUTPUT);
pinMode(7,OUTPUT);
}

void loop() {
digitalWrite(7, HIGH);
digitalWrite(2,HIGH);
delay(12000);//Ｙ绿灯亮
digitalWrite(3, HIGH);
digitalWrite(2, LOW);
delay(1000);//Ｙ黄灯亮
digitalWrite(3, LOW);
delay(1000);//Ｙ黄灯灭
digitalWrite(3, HIGH);
delay(1000);//Ｙ黄灯亮
digitalWrite(3, LOW);
delay(1000);//Ｙ黄灯灭
digitalWrite(3, HIGH);
delay(1000);//Ｙ黄灯亮
digitalWrite(3, LOW);
delay(1000);//Ｙ黄灯灭
digitalWrite(7, LOW);
digitalWrite(5, HIGH);
digitalWrite(4, HIGH);
delay(12000);//Ｘ绿灯亮
digitalWrite(7, LOW);
digitalWrite(6, HIGH);
digitalWrite(5, LOW);
delay(1000);//Ｘ黄灯亮
digitalWrite(6, LOW);
delay(1000);//Ｘ黄灯灭
digitalWrite(6, HIGH);
delay(1000);//Ｘ黄灯亮
digitalWrite(6, LOW);
delay(1000);//Ｘ黄灯灭
digitalWrite(6, HIGH);
delay(1000);//Ｘ黄灯亮
digitalWrite(6, LOW);
delay(1000);//Ｘ黄灯灭
}