const int LED1=1;
const int LED2=2;
const int LED3=3;
const int LED4=4;
const int LED5=5;
const int LED6=6;
const int LED7=7;
const int LED8=8;
const int LED9=9;


void setup() {
  pinMode(LED1,OUTPUT);
  pinMode(LED2,OUTPUT);
  pinMode(LED3,OUTPUT);
  pinMode(LED4,OUTPUT);
  pinMode(LED5,OUTPUT);
  pinMode(LED6,OUTPUT);
  pinMode(LED7,OUTPUT);
  pinMode(LED8,OUTPUT);
  pinMode(LED9,OUTPUT);

}

void loop() {
// Left to Right
  digitalWrite(LED1,HIGH);
  delay(200);

  digitalWrite(LED1,LOW);
  digitalWrite(LED2,HIGH);
  delay(200);

  digitalWrite(LED2,LOW);
  digitalWrite(LED3,HIGH);
  delay(200);
  
  digitalWrite(LED3,LOW);
  digitalWrite(LED4,HIGH);
  delay(200);

  digitalWrite(LED4,LOW);
  digitalWrite(LED5,HIGH);
  delay(200);

  digitalWrite(LED5,LOW);
  digitalWrite(LED6,HIGH);
  delay(200);

  digitalWrite(LED6,LOW);
  digitalWrite(LED7,HIGH);
  delay(200);

  digitalWrite(LED7,LOW);
  digitalWrite(LED8,HIGH);
  delay(200);

  digitalWrite(LED8,LOW);
  digitalWrite(LED9,HIGH);
  delay(200);

// Right to Left
  digitalWrite(LED9,LOW);
  digitalWrite(LED8,HIGH);
  delay(200);

  digitalWrite(LED8,LOW);
  digitalWrite(LED7,HIGH);
  delay(200);
  
  digitalWrite(LED7,LOW);
  digitalWrite(LED6,HIGH);
  delay(200);

  digitalWrite(LED6,LOW);
  digitalWrite(LED5,HIGH);
  delay(200);

  digitalWrite(LED5,LOW);
  digitalWrite(LED4,HIGH);
  delay(200);

  digitalWrite(LED4,LOW);
  digitalWrite(LED3,HIGH);
  delay(200);

  digitalWrite(LED3,LOW);
  digitalWrite(LED2,HIGH);
  delay(200);

  digitalWrite(LED2,LOW);
  digitalWrite(LED1,HIGH);
  delay(200);

  digitalWrite(LED1,LOW);
  delay(1000);

// End to Center (Normal)
  digitalWrite(LED9,HIGH);
  digitalWrite(LED1,HIGH);
  delay(1000);

  digitalWrite(LED9,LOW);
  digitalWrite(LED1,LOW);
  digitalWrite(LED8,HIGH);
  digitalWrite(LED2,HIGH);
  delay(1000);
   
  digitalWrite(LED8,LOW);
  digitalWrite(LED2,LOW);
  digitalWrite(LED7,HIGH);
  digitalWrite(LED3,HIGH);
  delay(1000);

  digitalWrite(LED7,LOW);
  digitalWrite(LED3,LOW);
  digitalWrite(LED6,HIGH);
  digitalWrite(LED4,HIGH);
  delay(1000);

  digitalWrite(LED6,LOW);
  digitalWrite(LED4,LOW);
  digitalWrite(LED5,HIGH);
  delay(1000);

// Returning (Normal)
  digitalWrite(LED5,LOW);
  digitalWrite(LED6,HIGH);
  digitalWrite(LED4,HIGH);
  delay(1000);

  digitalWrite(LED6,LOW);
  digitalWrite(LED4,LOW);
  digitalWrite(LED7,HIGH);
  digitalWrite(LED3,HIGH);
  delay(1000);

  digitalWrite(LED7,LOW);
  digitalWrite(LED3,LOW);
  digitalWrite(LED8,HIGH);
  digitalWrite(LED2,HIGH);
  delay(1000);

  digitalWrite(LED8,LOW);
  digitalWrite(LED2,LOW);
  digitalWrite(LED9,HIGH);
  digitalWrite(LED1,HIGH);
  delay(1000);

// End to Center (Slow)
  digitalWrite(LED9,HIGH);
  digitalWrite(LED1,HIGH);
  delay(2000);

  digitalWrite(LED9,LOW);
  digitalWrite(LED1,LOW);
  digitalWrite(LED8,HIGH);
  digitalWrite(LED2,HIGH);
  delay(2000);
   
  digitalWrite(LED8,LOW);
  digitalWrite(LED2,LOW);
  digitalWrite(LED7,HIGH);
  digitalWrite(LED3,HIGH);
  delay(2000);

  digitalWrite(LED7,LOW);
  digitalWrite(LED3,LOW);
  digitalWrite(LED6,HIGH);
  digitalWrite(LED4,HIGH);
  delay(2000);

  digitalWrite(LED6,LOW);
  digitalWrite(LED4,LOW);
  digitalWrite(LED5,HIGH);
  delay(2000);

// Returning (Slow)
  digitalWrite(LED5,LOW);
  digitalWrite(LED6,HIGH);
  digitalWrite(LED4,HIGH);
  delay(2000);

  digitalWrite(LED6,LOW);
  digitalWrite(LED4,LOW);
  digitalWrite(LED7,HIGH);
  digitalWrite(LED3,HIGH);
  delay(2000);

  digitalWrite(LED7,LOW);
  digitalWrite(LED3,LOW);
  digitalWrite(LED8,HIGH);
  digitalWrite(LED2,HIGH);
  delay(2000);

  digitalWrite(LED8,LOW);
  digitalWrite(LED2,LOW);
  digitalWrite(LED9,HIGH);
  digitalWrite(LED1,HIGH);
  delay(2000);
  
// End to Center (Fast)
  digitalWrite(LED9,HIGH);
  digitalWrite(LED1,HIGH);
  delay(200);

  digitalWrite(LED9,LOW);
  digitalWrite(LED1,LOW);
  digitalWrite(LED8,HIGH);
  digitalWrite(LED2,HIGH);
  delay(200);
   
  digitalWrite(LED8,LOW);
  digitalWrite(LED2,LOW);
  digitalWrite(LED7,HIGH);
  digitalWrite(LED3,HIGH);
  delay(200);

  digitalWrite(LED7,LOW);
  digitalWrite(LED3,LOW);
  digitalWrite(LED6,HIGH);
  digitalWrite(LED4,HIGH);
  delay(200);

  digitalWrite(LED6,LOW);
  digitalWrite(LED4,LOW);
  digitalWrite(LED5,HIGH);
  delay(200);

// Returning (Fast)
  digitalWrite(LED5,LOW);
  digitalWrite(LED6,HIGH);
  digitalWrite(LED4,HIGH);
  delay(200);

  digitalWrite(LED6,LOW);
  digitalWrite(LED4,LOW);
  digitalWrite(LED7,HIGH);
  digitalWrite(LED3,HIGH);
  delay(200);

  digitalWrite(LED7,LOW);
  digitalWrite(LED3,LOW);
  digitalWrite(LED8,HIGH);
  digitalWrite(LED2,HIGH);
  delay(200);

  digitalWrite(LED8,LOW);
  digitalWrite(LED2,LOW);
  digitalWrite(LED9,HIGH);
  digitalWrite(LED1,HIGH);
  delay(200);

  digitalWrite(LED9,LOW);
  digitalWrite(LED1,LOW);
  delay(1000);
}