void setup() {
  // put your setup code here, to run once:
  //initialize your bpin number
  //LED +ve pin can connect with Any pin of
  //LED -ve pin can connect with ground
  for(int i = 4; i <= 5; i++)
  {
    pinMode(i, OUTPUT);
  }
}

void loop() {
  for(int i = 5 ; i >= 3; i--) {
    digitalWrite(i, HIGH);
    delay(1000);
    digitalWrite(i, LOW);
    delay(1000);



  }
 



  // put your main code here, to run repeatedly:
 // code run forever
}