#define RED 1
#define YELLOW 5
#define GREEN 13
void setup(){
pinMode(RED,OUTPUT);
pinMode(YELLOW, OUTPUT);
pinMode(GREEN,OUTPUT);
}
void loop(){
digitalWrite(YELLOW,HIGH);
digitalWrite(RED,LOW);
digitalWrite(GREEN,LOW);
delay(500);
digitalWrite(RED, HIGH);
digitalWrite(YELLOW, LOW);
digitalWrite(GREEN,LOW);
delay(500);
digitalWrite(GREEN,HIGH);
digitalWrite(RED,LOW);
digitalWrite(YELLOW,LOW);
delay(500);
}