int LED_1=25;
int LED_2=27;
int LED_3=12;
int LED_4=13;

void setup() {
  pinMode(LED_1, OUTPUT);
  pinMode(LED_2, OUTPUT);
  pinMode(LED_3, OUTPUT);
  pinMode(LED_4, OUTPUT);
}

void loop() {
  digitalWrite(LED_1, 1);  
  digitalWrite(LED_2, 1);  
  digitalWrite(LED_3, HIGH);  
  digitalWrite(LED_4, HIGH);  
  delay(1000);                      
  digitalWrite(LED_1, 0);  
  digitalWrite(LED_2, 0);  
  digitalWrite(LED_3, LOW);  
  digitalWrite(LED_4, LOW);     
  delay(1000);                      
}