int ledPin = 10;
void setup() {
pinMode(ledPin, OUTPUT);
}
void loop() {
 //3 quick blinks to represent "S" again 
for(int x=0;x<3;x++){
  digitalWrite(ledPin,HIGH);
  delay (150);
  digitalWrite(ledPin,LOW);
  delay(100);
}

//100 milliseconds delay between each letter 
delay(100);

//3 quick blinks to represent "O"
for(int x=0;x<3;x++){
  digitalWrite(ledPin,HIGH);
  delay (400);
  digitalWrite(ledPin,LOW);
  delay(100);
}

//100 milliseconds delay between each letter 
delay(100);

 //3 quick blinks to represent "S" again
for(int x=0;x<3;x++){
  digitalWrite(ledPin,HIGH);
  delay (150);
  digitalWrite(ledPin,LOW);
  delay(100);
}

//wait 5 seconds to repeat the next S.O.S signal
 delay(5000);
}