//Coded By: Nitin Rajput

int LEDPins[] = {13, 12, 8, 4, 2};      

void setup() 
{
  for (int PIN = 0; PIN < 6; PIN= PIN + 1)   
  {  
    pinMode(LEDPins[PIN], OUTPUT);  
  } 
}

void loop() 
{
    for(int PIN=0; PIN<=5; PIN++) 
    {  
        digitalWrite(LEDPins[PIN], HIGH);  
        delay(500);   
        digitalWrite(LEDPins[PIN], LOW);  
    }  
    for(int PIN=5; PIN>=0; PIN--)  
    {   
      digitalWrite(LEDPins[PIN], HIGH);  
      delay(500);  
      digitalWrite(LEDPins[PIN], LOW);   
    }  
}