#define pinA 2
#define pinB 3
#define pinC 4
#define pinD 5

#define pinBotao 10

int numero = 4;
boolean botaoAtu = false;
boolean botaoAnt = false;

void setup() {
  pinMode(pinBotao, INPUT_PULLUP);
  pinMode(pinA, OUTPUT);
  pinMode(pinB, OUTPUT);
  pinMode(pinC, OUTPUT);
  pinMode(pinD, OUTPUT);
}

void loop() {
  botaoAtu = digitalRead(pinBotao);

  if (botaoAtu && !botaoAnt) {
     numero++;

     if (numero > 3) {
        numero = 0;
     }
  }
  botaoAnt = botaoAtu;

  switch (numero) {
      case 0:
        digitalWrite(pinA, HIGH);
        digitalWrite(pinB, LOW);
        digitalWrite(pinC, LOW);
        digitalWrite(pinD, LOW);
        delay(100);
        break;

      case 1:
        digitalWrite(pinA, LOW);
        digitalWrite(pinB, HIGH);
        digitalWrite(pinC, LOW);
        digitalWrite(pinD, LOW);
        delay(100);
        break;

      case 2:
        digitalWrite(pinA, LOW);
        digitalWrite(pinB, LOW);
        digitalWrite(pinC, HIGH);
        digitalWrite(pinD, LOW);
        delay(100);
        break;

      case 3:
        digitalWrite(pinA, LOW);
        digitalWrite(pinB, LOW);
        digitalWrite(pinC, LOW);
        digitalWrite(pinD, HIGH);
        delay(100);
        break;
  }
}