int Rled=8;
int Yled=9;
int Gled=10;



void setup() {
pinMode (Rled,OUTPUT);
pinMode (Yled,OUTPUT);
pinMode (Gled,OUTPUT);


}

void loop() {
  digitalWrite (Rled,HIGH);
  delay(2000);
  digitalWrite (Rled,LOW);
  digitalWrite (Yled,HIGH);
  delay(3000);
  digitalWrite (Yled,LOW);
  digitalWrite (Gled,HIGH);
  delay(6000);
  digitalWrite (Gled,LOW);

}