void setup() {
  pinMode(13, OUTPUT);
  pinMode(12, OUTPUT);
  pinMode(11, OUTPUT);
  pinMode(10, OUTPUT);
}

void loop() 
{
{
  digitalWrite(13, HIGH);
  delay(1000);
  digitalWrite(13,LOW);
  delay(1000);
}
{
  digitalWrite(12, HIGH);
  delay(2000);
  digitalWrite(12,LOW);
  delay(2000);
}
{
  digitalWrite(11, HIGH);
  delay(3000);
  digitalWrite(11,LOW);
  delay(3000);
}
{
  digitalWrite(10, HIGH);
  delay(4000);
  digitalWrite(10,LOW);
  delay(4000);
}
}