int pin1=7;
int pin2=8;
int pin3=12;
int pin4=13;
int delaybet=500;


void setup() {
  // put your setup code here, to run once:
pinMode(13,OUTPUT);
pinMode(12,OUTPUT);
pinMode(8,OUTPUT);
pinMode(7,OUTPUT);
}

void loop() {
  // put your main code here, to run repeatedly:
digitalWrite(pin1,LOW);
digitalWrite(pin2,LOW);
digitalWrite(pin3,LOW);
digitalWrite(pin4,LOW);
delay(delaybet);

digitalWrite(pin1,HIGH);
digitalWrite(pin2,LOW);
digitalWrite(pin3,LOW);
digitalWrite(pin4,LOW);
delay(delaybet);

digitalWrite(pin1,LOW);
digitalWrite(pin2,HIGH);
digitalWrite(pin3,LOW);
digitalWrite(pin4,LOW);
delay(delaybet);

digitalWrite(pin1,HIGH);
digitalWrite(pin2,HIGH);
digitalWrite(pin3,LOW);
digitalWrite(pin4,LOW);
delay(delaybet);

digitalWrite(pin1,LOW);
digitalWrite(pin2,LOW);
digitalWrite(pin3,HIGH);
digitalWrite(pin4,LOW);
delay(delaybet);

digitalWrite(pin1,HIGH);
digitalWrite(pin2,LOW);
digitalWrite(pin3,HIGH);
digitalWrite(pin4,LOW);
delay(delaybet);

digitalWrite(pin1,LOW);
digitalWrite(pin2,HIGH);
digitalWrite(pin3,HIGH);
digitalWrite(pin4,LOW);
delay(delaybet);

digitalWrite(pin1,HIGH);
digitalWrite(pin2,HIGH);
digitalWrite(pin3,HIGH);
digitalWrite(pin4,LOW);
delay(delaybet);

digitalWrite(pin1,LOW);
digitalWrite(pin2,LOW);
digitalWrite(pin3,LOW);
digitalWrite(pin4,HIGH);
delay(delaybet);

digitalWrite(pin1,HIGH);
digitalWrite(pin2,LOW);
digitalWrite(pin3,LOW);
digitalWrite(pin4,HIGH);
delay(delaybet);

digitalWrite(pin1,LOW);
digitalWrite(pin2,HIGH);
digitalWrite(pin3,LOW);
digitalWrite(pin4,HIGH);
delay(delaybet);

digitalWrite(pin1,HIGH);
digitalWrite(pin2,HIGH);
digitalWrite(pin3,LOW);
digitalWrite(pin4,HIGH);
delay(delaybet);

digitalWrite(pin1,LOW);
digitalWrite(pin2,LOW);
digitalWrite(pin3,HIGH);
digitalWrite(pin4,HIGH);
delay(delaybet);

digitalWrite(pin1,HIGH);
digitalWrite(pin2,LOW);
digitalWrite(pin3,HIGH);
digitalWrite(pin4,HIGH);
delay(delaybet);

digitalWrite(pin1,LOW);
digitalWrite(pin2,HIGH);
digitalWrite(pin3,HIGH);
digitalWrite(pin4,HIGH);
delay(delaybet);

digitalWrite(pin1,HIGH);
digitalWrite(pin2,HIGH);
digitalWrite(pin3,HIGH);
digitalWrite(pin4,HIGH);
delay(delaybet);
}