void setup() {
  // put your setup code here, to run once:
  Serial.begin (9600);

  //LED Output
  pinMode(13, OUTPUT);
  pinMode(12, OUTPUT);
  pinMode(11, OUTPUT);
  pinMode(10, OUTPUT);
  pinMode(9, OUTPUT);
  //Switch input
  pinMode(8, INPUT);

  //set the pull-up on the switch
  digitalWrite(8, HIGH);

  //seed the random number generator
  randomSeed(millis());

  //wait random time from 1 to 3 seconds
  //delay(random(1000,3000));
  delay(3000);


  //turn the light on
  digitalWrite(9, HIGH);
  delay(1000);
  digitalWrite(10, HIGH);
  delay(1000);
  digitalWrite(11, HIGH);
  delay(1000);
  digitalWrite(12, HIGH);
  delay(1000);
  digitalWrite(13, HIGH);
  delay(1000);

//wait random time from 3 to 5 seconds
  delay(random(3000,5000));

  digitalWrite(13,LOW);
  digitalWrite(12,LOW);
  digitalWrite(11,LOW);
  digitalWrite(10,LOW);
  digitalWrite(9,LOW);


  //get the start time
  long start = millis();

  //wait while the switch isn't pressed
  while(digitalRead(8))

  {}
 

//print out the data
Serial.print ("Your reaction time:");
Serial.println((millis() - start)/1000.0);
}

void loop() {
  // put your main code here, to run repeatedly:

}