void  setup()         {
  pinMode(13, OUTPUT);
  pinMode( 11, OUTPUT);
  pinMode(12, OUTPUT);
  pinMode(2, INPUT);
  digitalWrite(     13, LOW);
  digitalWrite(11, LOW);
  digitalWrite(     12, LOW);
}

void  loop()   {

  if (digitalRead(   2   ) ==HIGH){
    for(int   i =0;i<5;i++){
    digitalWrite(  11, LOW);
    digitalWrite(     12, HIGH);
    delay(500);
    digitalWrite(     12, LOW);
    delay(  500);
   }
  
   digitalWrite(     13, HIGH);
   delay(20000);
   digitalWrite(     13, LOW );
  }
else  {
 digitalWrite(     11, HIGH);
 }
}