// Arduino Seven Segment Display (Common Cathode)
// Segments a–g connected to Arduino pins 2–8

int segPins[7] = {2, 3, 4, 5, 6, 7, 8};

// Digit patterns for 0–9 (1 = ON, 0 = OFF)
int digits[10][7] = {
  {1,1,1,1,1,1,0}, // 0
  {0,1,1,0,0,0,0}, // 1
  {1,1,0,1,1,0,1}, // 2
  {1,1,1,1,0,0,1}, // 3
  {0,1,1,0,0,1,1}, // 4
  {1,0,1,1,0,1,1}, // 5
  {1,0,1,1,1,1,1}, // 6
  {1,1,1,0,0,0,0}, // 7
  {1,1,1,1,1,1,1}, // 8
  {1,1,1,1,0,1,1}  // 9
};

void setup() {
  // Set all pins as OUTPUT
  for (int i = 0; i < 7; i++) {
    pinMode(segPins[i], OUTPUT);
  }
}

void loop() {
  // Loop through numbers 0–9
  for (int num = 0; num < 10; num++) {
    displayDigit(num);
    delay(1000); // Hold each number for 1 second
  }
}

// Function to light up segments for a given digit
void displayDigit(int num) {
  for (int i = 0; i < 7; i++) {
    digitalWrite(segPins[i], digits[num][i]);
  }
}