int pulsador[10] = {14, 15, 16, 17, 18, 19, 6, 7, 8, 9};
int flag[10] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0};

void setup() {
  // initialize serial communications at 9600 bps:
  for (int i=0; i<9; i++) pinMode(pulsador[i], INPUT);
  Serial.begin(19200); 
}

void loop() {
  
  for (int i=0; i<10; i++) 
  {
    if((!digitalRead(pulsador[i]))&&(!flag[i]))
    {
      flag[i]=1;
      Serial.print(i,BYTE);
    }
    else if((digitalRead(pulsador[i]))&&(flag[i])) flag[i]=0;
  }
  delay(10);                      
}