const int ledPins[] = {2, 3, 4, 5, 6, 7, 8, 9, 10, 11};
const int numPatterns = 10;
int currentPattern = 0;

void setup() {
  for (int i = 0; i < 10; i++) {
    pinMode(ledPins[i], OUTPUT);
  }
}

void loop() {
  switch (currentPattern) {
    case 0: pattern0(); break;
    case 1: pattern1(); break;
    case 2: pattern2(); break;
    case 3: pattern3(); break;
    case 4: pattern4(); break;
    case 5: pattern5(); break;
    case 6: pattern6(); break;
    case 7: pattern7(); break;
    case 8: pattern8(); break;
    case 9: pattern9(); break;
  }

  currentPattern = (currentPattern + 1) % numPatterns;
  delay(1000);  // Change pattern every second
}

void pattern0() {
  // All LEDs on and off
  for (int i = 0; i < 10; i++) {
    digitalWrite(ledPins[i], HIGH);
  }
  delay(500);
  for (int i = 0; i < 10; i++) {
    digitalWrite(ledPins[i], LOW);
  }
  delay(500);
}

void pattern1() {
  // One by one on and off
  for (int i = 0; i < 10; i++) {
    digitalWrite(ledPins[i], HIGH);
    delay(100);
    digitalWrite(ledPins[i], LOW);
    delay(100);
  }
}

void pattern2() {
  // Two at a time
  for (int i = 0; i < 9; i += 2) {
    digitalWrite(ledPins[i], HIGH);
    digitalWrite(ledPins[i + 1], HIGH);
    delay(200);
    digitalWrite(ledPins[i], LOW);
    digitalWrite(ledPins[i + 1], LOW);
    delay(200);
  }
}

void pattern3() {
  // Alternate LEDs
  for (int i = 0; i < 10; i += 2) {
    digitalWrite(ledPins[i], HIGH);
  }
  delay(500);
  for (int i = 1; i < 10; i += 2) {
    digitalWrite(ledPins[i], HIGH);
  }
  delay(500);
  for (int i = 0; i < 10; i++) {
    digitalWrite(ledPins[i], LOW);
  }
  delay(500);
}

void pattern4() {
  // Chase effect
  for (int i = 0; i < 10; i++) {
    digitalWrite(ledPins[i], HIGH);
    delay(100);
    digitalWrite(ledPins[i], LOW);
  }
}

void pattern5() {
  // Ping-pong effect
  for (int i = 0; i < 10; i++) {
    digitalWrite(ledPins[i], HIGH);
    delay(100);
    digitalWrite(ledPins[i], LOW);
  }
  for (int i = 8; i > 0; i--) {
    digitalWrite(ledPins[i], HIGH);
    delay(100);
    digitalWrite(ledPins[i], LOW);
  }
}

void pattern6() {
  // Random LEDs on and off
  for (int i = 0; i < 10; i++) {
    int randomLed = random(0, 10);
    digitalWrite(ledPins[randomLed], HIGH);
    delay(100);
    digitalWrite(ledPins[randomLed], LOW);
  }
}

void pattern7() {
  // Knight rider effect
  for (int i = 0; i < 10; i++) {
    digitalWrite(ledPins[i], HIGH);
    if (i > 0) digitalWrite(ledPins[i - 1], LOW);
    delay(100);
  }
  for (int i = 8; i >= 0; i--) {
    digitalWrite(ledPins[i], HIGH);
    if (i < 9) digitalWrite(ledPins[i + 1], LOW);
    delay(100);
  }
}

void pattern8() {
  // Two LEDs moving towards center
  for (int i = 0; i < 5; i++) {
    digitalWrite(ledPins[i], HIGH);
    digitalWrite(ledPins[9 - i], HIGH);
    delay(200);
    digitalWrite(ledPins[i], LOW);
    digitalWrite(ledPins[9 - i], LOW);
  }
}

void pattern9() {
  // Blink all LEDs twice
  for (int j = 0; j < 2; j++) {
    for (int i = 0; i < 10; i++) {
      digitalWrite(ledPins[i], HIGH);
    }
    delay(200);
    for (int i = 0; i < 10; i++) {
      digitalWrite(ledPins[i], LOW);
    }
    delay(200);
  }
}