5 Digit Arduino Nano Binary Counter/ LED Matrix

//5 Digit Arduino Nano Binary Counter
//Counter 1-99999
/* I did this project by using 5x7 LED Matrix with its pins 1, 3, 10, 7, 8 for common cathodes to Arduino pins 8, 9, 6, 17(A3) & 19(A5) respectively while anodes matrix pins 9, 2, 11 & 12 to Arduino pins 7, 18(A4), 5 & 4 correspondingly. */
#define A 7
#define B 18
#define C 5
#define D 4
// Pins driving common cathodes
#define CC1 8
#define CC2 9
#define CC3 6
#define CC4 17
#define CC5 19
// Pins for A, B, C, D in sequence
const int segs[4] = {7, 18, 5, 4};
// Segments that make each number
const byte numbers[10] = {0b0000, 0b0001, 0b0010, 0b0011, 0b0100, 0b0101, 0b0110, 0b0111, 0b1000, 0b1001};
 void setup() {
  pinMode(7, OUTPUT);
  pinMode(18, OUTPUT);
  pinMode(5, OUTPUT);
  pinMode(4, OUTPUT);
  pinMode(8, OUTPUT);
  pinMode(9, OUTPUT);
  pinMode(6, OUTPUT);
  pinMode(17, OUTPUT);
  pinMode(19, OUTPUT);
}
void loop() {
  for (int digit1=0; digit1 < 10; digit1++) {
    for (int digit2=0; digit2 < 10; digit2++) {
      for(int digit3=0; digit3 < 10; digit3++) {
        for(int digit4=0; digit4 < 10; digit4++) {
          for(int digit5=0; digit5 < 10; digit5++) {
      unsigned long startTime = millis();
      for (unsigned long elapsed=0; elapsed < 600; elapsed = millis() - startTime) {
        lightDigit1(numbers[digit1]);
        delay(5);
        lightDigit2(numbers[digit2]);
        delay(5);
        lightDigit3(numbers[digit3]);
        delay(5);
        lightDigit4(numbers[digit4]);
        delay(5);
        lightDigit5(numbers[digit5]);
        delay(5);
      }
      }
    }
  }
}
}
}
void lightDigit1(byte number) {
  digitalWrite(CC1, HIGH);
  digitalWrite(CC2, HIGH);
  digitalWrite(CC3, HIGH);
  digitalWrite(CC4, HIGH);
  digitalWrite(CC5, LOW);
  lightSegments(number);
}
void lightDigit2(byte number) {
  digitalWrite(CC1, HIGH);
  digitalWrite(CC2, HIGH);
  digitalWrite(CC3, HIGH);
  digitalWrite(CC4, LOW);
  digitalWrite(CC5, HIGH);
  lightSegments(number);
}
void lightDigit3(byte number) {
  digitalWrite(CC1, HIGH);
  digitalWrite(CC2, HIGH);
  digitalWrite(CC3, LOW);
  digitalWrite(CC4, HIGH);
  digitalWrite(CC5, HIGH);
  lightSegments(number);
}
void lightDigit4(byte number) {
  digitalWrite(CC1, HIGH);
  digitalWrite(CC2, LOW);
  digitalWrite(CC3, HIGH);
  digitalWrite(CC4, HIGH);
  digitalWrite(CC5, HIGH);
  lightSegments(number);
}
void lightDigit5(byte number) {
  digitalWrite(CC1, LOW);
  digitalWrite(CC2, HIGH);
  digitalWrite(CC3, HIGH);
  digitalWrite(CC4, HIGH);
  digitalWrite(CC5, HIGH);
  lightSegments(number);
}


void lightSegments(byte number) {
  for (int i = 0; i < 4; i++) {
    int bit = bitRead(number, i);
    digitalWrite(segs[i], bit);
  }
}