// Define pins for the segments
int segmentPins[] = {6, 7, 8, 9, 10, 11, 12};

// Define pins for the common cathodes/anodes
int digitPins[] = {2, 3, 4, 5};

void setup() {
  // Set up segment pins as outputs using a loop
  for (int i = 0; i < 7; i++) {
    pinMode(segmentPins[i], OUTPUT);
  }

  // Set up digit pins as outputs using a loop
  for (int i = 0; i < 4; i++) {
    pinMode(digitPins[i], OUTPUT);
  }
}

void loop() {
  // Loop through each digit pin to display the numbers
  for (int digit = 0; digit < 4; digit++) {
    // Activate the current digit pin
    digitalWrite(digitPins[digit], HIGH);

    // Display numbers 0 to 9
    for (int i = 0; i < 10; i++) {
      displayNumber(i);
      delay(500);
    }

    // Deactivate the current digit pin
    digitalWrite(digitPins[digit], LOW);
  }
}

// Function to display a digit on the seven-segment display
void displayNumber(int number) {
  switch (number) {
    case 0:
      displaySegment(0,0,0,0,0,0,1); // Display 0
      break;
    case 1:
      displaySegment(1,0,0,1,1,1,1);// Display 1
      break;
    case 2:
      displaySegment(0,0,1,0,0,1,0); // Display 2
      break;
    case 3:
      displaySegment(0,0,0,0,1,1,0); // Display 3
      break;
    case 4:
      displaySegment(1,0,0,1,1,0,0); // Display 4
      break;
    case 5:
      displaySegment(0,1,0,0,1,0,0); // Display 5
      break;
    case 6:
      displaySegment(0,1,0,0,0,0,0); // Display 6
      break;
    case 7:
      displaySegment(0,0,0,1,1,1,1); // Display 7
      break;
    case 8:
      displaySegment(0,0,0,0,0,0,0); // Display 8
      break;
    case 9:
      displaySegment(0,0,0,0,1,0,0); // Display 9
      break;
  }
}

// Function to set segment pins based on the digit to be displayed
void displaySegment(int a, int b, int c, int d, int e, int f, int g) {
  digitalWrite(segmentPins[0], a); //  logic for common anode display
  digitalWrite(segmentPins[1], b); //  logic for common anode display
  digitalWrite(segmentPins[2], c); //  logic for common anode display
  digitalWrite(segmentPins[3], d); //  logic for common anode display
  digitalWrite(segmentPins[4], e); //  logic for common anode display
  digitalWrite(segmentPins[5], f); //  logic for common anode display
  digitalWrite(segmentPins[6], g); //  logic for common anode display
}