const int a = 2;
const int b = 3;
const int f = 4;
const int g = 5;
const int c = A2;
const int d = A1;
const int e = A0;
const int pulsador_suma = 6;
const int pulsador_resta = 7;
const int suma;
const int resta;

int contador = 0;
void setup () {
  pinMode (a, OUTPUT);
  pinMode (b, OUTPUT);
  pinMode (c, OUTPUT);
  pinMode (d, OUTPUT);
  pinMode (e, OUTPUT);
  pinMode (f, OUTPUT);
  pinMode (g, OUTPUT);
  pinMode (pulsador_suma, INPUT_PULLUP);
  pinMode (pulsador_resta, INPUT_PULLUP);
}
void loop () {
   if (digitalRead(pulsador_suma) == LOW) {
    delay (200);
    contador ++;
    if (contador == 10) {
      contador = 0;
    }
   }
   if (digitalRead (pulsador_resta) == LOW) {
    delay (200);
    contador--;
    if (contador == -1) {
      contador = 9;
    }
  }
  if (contador == 0) {
    digitalWrite (a, LOW);
    digitalWrite (b, LOW);
    digitalWrite (c, LOW);
    digitalWrite (d, LOW);
    digitalWrite (e, LOW);
    digitalWrite (f, LOW);
    digitalWrite (g, HIGH);
    delay (200);
  }
  if (contador == 1) {
    digitalWrite (a, HIGH);
    digitalWrite (b, LOW);
    digitalWrite (c, LOW);
    digitalWrite (d, HIGH);
    digitalWrite (e, HIGH);
    digitalWrite (f, HIGH);
    digitalWrite (g, HIGH);
  }
  if (contador == 2) {
    digitalWrite (a, LOW);
    digitalWrite (b, LOW);
    digitalWrite (c, HIGH);
    digitalWrite (d, LOW);
    digitalWrite (e, LOW);
    digitalWrite (f, HIGH);
    digitalWrite (g, LOW);
  }
  if (contador == 3) {
    digitalWrite (a, LOW);
    digitalWrite (b, LOW);
    digitalWrite (c, LOW);
    digitalWrite (d, LOW);
    digitalWrite (e, HIGH);
    digitalWrite (f, HIGH);
    digitalWrite (g, LOW);
  }
  if (contador == 4) {
    digitalWrite (a, HIGH);
    digitalWrite (b, LOW);
    digitalWrite (c, LOW);
    digitalWrite (d, HIGH);
    digitalWrite (e, HIGH);
    digitalWrite (f, LOW);
    digitalWrite (g, LOW);
  }
  if (contador == 5) {
    digitalWrite (a, LOW);
    digitalWrite (b, HIGH);
    digitalWrite (c, LOW);
    digitalWrite (d, LOW);
    digitalWrite (e, HIGH);
    digitalWrite (f, LOW);
    digitalWrite (g, LOW);
  }
  if (contador == 6) {
    digitalWrite (a, LOW);
    digitalWrite (b, HIGH);
    digitalWrite (c, LOW);
    digitalWrite (d, LOW);
    digitalWrite (e, LOW);
    digitalWrite (f, LOW);
    digitalWrite (g, LOW);
  }
  if (contador == 7) {
    digitalWrite (a, LOW);
    digitalWrite (b, LOW);
    digitalWrite (c, LOW);
    digitalWrite (d, HIGH);
    digitalWrite (e, HIGH);
    digitalWrite (f, HIGH);
    digitalWrite (g, HIGH);
  }
  if (contador == 8) {
    digitalWrite (a, LOW);
    digitalWrite (b, LOW);
    digitalWrite (c, LOW);
    digitalWrite (d, LOW);
    digitalWrite (e, LOW);
    digitalWrite (f, LOW);
    digitalWrite (g, LOW);
  }
  if (contador == 9) {
    digitalWrite (a, LOW);
    digitalWrite (b, LOW);
    digitalWrite (c, LOW);
    digitalWrite (d, HIGH);
    digitalWrite (e, HIGH);
    digitalWrite (f, LOW);
    digitalWrite (g, LOW);
  }
}