int led0 = 0;
int led1 = 1;
int led2 = 2;
int led3 = 3;
int led4 = 4;
int led5 = 5;
int timer = 40;
int count = 5;


void setup(){
  pinMode(led0, OUTPUT);
  pinMode(led1, OUTPUT);
  pinMode(led2, OUTPUT);
  pinMode(led3, OUTPUT);
  pinMode(led4, OUTPUT);
  pinMode(led5, OUTPUT);
}

void loop() {

count = 5;
 while(count >= 0) {
   digitalWrite(count, HIGH);
   delay(timer);
   digitalWrite(count, LOW);
   delay(timer);
   count = count -1;
 }
 while(count <= 5) {
   digitalWrite(count, HIGH);
   delay(timer);
   digitalWrite(count, LOW);
   delay(timer);
   count = count +1;
 }


    
}