#define green 7
#define yellow 6
#define red 5
void setup()
{
pinMode(5, OUTPUT);
pinMode(6, OUTPUT);
pinMode(7, OUTPUT);
}
void loop() {
digitalWrite(5, HIGH);
digitalWrite(6, LOW);
digitalWrite(7, LOW);
delay(3000);
digitalWrite(5, LOW);
digitalWrite(6, HIGH);
digitalWrite(7, LOW);
delay(3000);
digitalWrite(5, LOW);
digitalWrite(6, LOW);
digitalWrite(7, HIGH);
delay(3000);
}