//This shows how to use the switch case in arduino with LED
int led;
int delayTime =150;
void setup()   

{  
  // initialize serial communication:  
  Serial.begin(9600);  
  // initializing the LED pins:  
  for (int LEDpin = 8; LEDpin <=13 ; LEDpin++) {  
    pinMode(LEDpin, OUTPUT);  
    // here, we have used for loop for initialization  
  }  
}  
void loop()   
{  
  for(int i=1; i<=7; i++){
    led=i; // this represent the differen cases  
    switch (led)   
    {  
      case 1:  
        digitalWrite(8, HIGH);  
        break;  
      case 2:  
        digitalWrite(9, HIGH);  
        break;  
      case 3:  
        digitalWrite(10, HIGH);  
        break; 
      case 4:  
        digitalWrite(11, HIGH);  
        break;  
       case 5:  
        digitalWrite(12, HIGH);  
        break;  
      case 6:  
        digitalWrite(13, HIGH);  
        break;  
      default:  
        // turn all the LEDs off if all the above cases does not matches:  
        for (int LEDpin = 8; LEDpin <=13; LEDpin++)   
        {  
          digitalWrite(LEDpin, LOW);  
        }  
    }  
    delay(delayTime);
  }
  }