void setup() {
 pinMode (33, OUTPUT);
pinMode (14, OUTPUT);
pinMode (25,  OUTPUT);
pinMode (12, OUTPUT);
}



void loop() {
  digitalWrite (33, 1);
delay (500);
digitalWrite (33, 0);
digitalWrite (14, 1);
delay (500);
digitalWrite (14, 0);
digitalWrite (25, 1);
delay (500);
digitalWrite (25,0);
digitalWrite (12, 1);
delay (500);
digitalWrite (12,0);
}