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public class ArrayApp {
  public static boolean checkIfCircularArrayHasCycle(int[] arr) {
    if (arr.length <= 1) {
      return false;
    }

    for (int i = 0; i < arr.length; i++) {
      if (arr[i] == 0) continue;  // Skip visited elements

      int slow, fast;
      slow = fast = i;
      boolean ifForward = arr[i] > 0;

      while (true) {
        slow = getNextPosition(arr, slow, ifForward);
        if (slow == -1) break;

        fast = getNextPosition(arr, fast, ifForward);
        if (fast == -1) break;

        fast = getNextPosition(arr, fast, ifForward);
        if (fast == -1) break;

        if (slow == fast) {
          return true;
        }

        arr[slow] = 0;  // Mark as visited to avoid redundant work
      }
    }
    return false;
  }

  private static int getNextPosition(int[] arr, int index, boolean ifForward) {
    boolean direction = arr[index] >= 0;

    if (direction != ifForward) {
      return -1;
    }

    int nextIndex = (index + arr[index]) % arr.length;
    if (nextIndex < 0) {
      nextIndex = nextIndex + arr.length;
    }

    if (nextIndex == index) {
      return -1;
    }

    return nextIndex;
  }

  public static void main(String[] args) {
    int[] arr = {1, 1, 2, 1, 2};
    System.out.println(ArrayApp.checkIfCircularArrayHasCycle(arr)); // Output: true
  }
}