void setup() {
  // Traffic lights
  pinMode(2, OUTPUT); // Red
  pinMode(3, OUTPUT); // Yellow
  pinMode(4, OUTPUT); // Green

  // 7-segment display
  pinMode(5, OUTPUT); // a
  pinMode(6, OUTPUT); // b
  pinMode(7, OUTPUT); // c
  pinMode(8, OUTPUT); // d
  pinMode(9, OUTPUT); // e
  pinMode(10, OUTPUT); // f
  pinMode(11, OUTPUT); // g
}

void loop() {
  // Green ON
  digitalWrite(2, LOW);
  digitalWrite(3, LOW);
  digitalWrite(4, HIGH);
  countdown();  // 9 to 0
  digitalWrite(4, LOW);

  // Yellow blinks 3 times
  for (int i = 0; i < 3; i++) {
    digitalWrite(3, HIGH);
    delay(500);
    digitalWrite(3, LOW);
    delay(500);
  }

  // Red blinks 3 times
  for (int i = 0; i < 3; i++) {
    digitalWrite(2, HIGH);
    delay(500);
    digitalWrite(2, LOW);
    delay(500);
  }

  // Red ON for 3 seconds
  digitalWrite(2, HIGH);
  showDigit0();
  delay(3000);
}

// Functions for each digit (without array)
void showDigit0() {
  digitalWrite(5, HIGH);  // a
  digitalWrite(6, HIGH);  // b
  digitalWrite(7, HIGH);  // c
  digitalWrite(8, HIGH);  // d
  digitalWrite(9, HIGH);  // e
  digitalWrite(10, HIGH); // f
  digitalWrite(11, LOW);  // g
}

void showDigit1() {
  digitalWrite(5, LOW);
  digitalWrite(6, HIGH);
  digitalWrite(7, HIGH);
  digitalWrite(8, LOW);
  digitalWrite(9, LOW);
  digitalWrite(10, LOW);
  digitalWrite(11, LOW);
}

void showDigit2() {
  digitalWrite(5, HIGH);
  digitalWrite(6, HIGH);
  digitalWrite(7, LOW);
  digitalWrite(8, HIGH);
  digitalWrite(9, HIGH);
  digitalWrite(10, LOW);
  digitalWrite(11, HIGH);
}

void showDigit3() {
  digitalWrite(5, HIGH);
  digitalWrite(6, HIGH);
  digitalWrite(7, HIGH);
  digitalWrite(8, HIGH);
  digitalWrite(9, LOW);
  digitalWrite(10, LOW);
  digitalWrite(11, HIGH);
}

void showDigit4() {
  digitalWrite(5, LOW);
  digitalWrite(6, HIGH);
  digitalWrite(7, HIGH);
  digitalWrite(8, LOW);
  digitalWrite(9, LOW);
  digitalWrite(10, HIGH);
  digitalWrite(11, HIGH);
}

void showDigit5() {
  digitalWrite(5, HIGH);
  digitalWrite(6, LOW);
  digitalWrite(7, HIGH);
  digitalWrite(8, HIGH);
  digitalWrite(9, LOW);
  digitalWrite(10, HIGH);
  digitalWrite(11, HIGH);
}

void showDigit6() {
  digitalWrite(5, HIGH);
  digitalWrite(6, LOW);
  digitalWrite(7, HIGH);
  digitalWrite(8, HIGH);
  digitalWrite(9, HIGH);
  digitalWrite(10, HIGH);
  digitalWrite(11, HIGH);
}

void showDigit7() {
  digitalWrite(5, HIGH);
  digitalWrite(6, HIGH);
  digitalWrite(7, HIGH);
  digitalWrite(8, LOW);
  digitalWrite(9, LOW);
  digitalWrite(10, LOW);
  digitalWrite(11, LOW);
}

void showDigit8() {
  digitalWrite(5, HIGH);
  digitalWrite(6, HIGH);
  digitalWrite(7, HIGH);
  digitalWrite(8, HIGH);
  digitalWrite(9, HIGH);
  digitalWrite(10, HIGH);
  digitalWrite(11, HIGH);
}

void showDigit9() {
  digitalWrite(5, HIGH);
  digitalWrite(6, HIGH);
  digitalWrite(7, HIGH);
  digitalWrite(8, HIGH);
  digitalWrite(9, LOW);
  digitalWrite(10, HIGH);
  digitalWrite(11, HIGH);
}

void countdown() {
  showDigit9(); delay(1000);
  showDigit8(); delay(1000);
  showDigit7(); delay(1000);
  showDigit6(); delay(1000);
  showDigit5(); delay(1000);
  showDigit4(); delay(1000);
  showDigit3(); delay(1000);
  showDigit2(); delay(1000);
  showDigit1(); delay(1000);
  showDigit0(); delay(1000);
}