int pinC = 17;
 void showAll(){ 
   digitalWrite(pinC,1);
 }
 void showOFF(){
  digitalWrite(pinC, 0);
 }
 void showC(){
  digitalRead(pinC, 1);
 }
void setup(){
  pinMode(pinC, OUTPUT);
}
void loop(){
  showAll();
  delay(500);
  showOFF();
  delay(500);
  showAll();
  delay(500);
  showOFF();
  delay(500);
  showAll();
  delay(500);
  showOFF();
  delay(500);
  showAll();
  delay(500);
  showOFF();
  delay(500);
}