const byte numeral[10] =
{
  B11111101, //0
  B01100001, //1
  B11011011, //2
  B11110011, //3
  B01100111, //4
  B10110111, //5
  B10111111, //6
  B11100001, //7
  B11111111, //8
  B11110111, //9
};
const int segmentpins[8] = {5,9,8,7,6,4,3,2};
void setup() {
  // put your setup code here, to run once:
 for(int i=0; i<8; i++){
  pinMode(segmentpins[i], OUTPUT);
 }
}

void loop() {
  // put your main code here, to run repeatedly:
for(int i=9; i>=0; i--){
  showdigit(i);
  delay(1000);
}
delay(2000);
}
void showdigit(int number){
  boolean isBitSet;
  for(int segment = 1; segment < 8; segment++){
    if(number<0||number>9){
      isBitSet = 0; //segment mati
    } else{
      isBitSet =bitRead(numeral[number], segment);
    }
    isBitSet = !isBitSet;
    digitalWrite(segmentpins[segment], isBitSet);
  }
}