def remove_folder(folders: list[str], folder_to_rm: str) -> list[str]:
    if not folders:
        return folders

    if not isinstance(folder_to_rm, str):
        raise ValueError('Enter a valid folder name')

    new_folders = []
    for i, folder in enumerate(folders):
        folder_names = folder.split('/')[1:]
        if folder_names[0] == folder_to_rm:
            del folders[i]
            continue
        for i, folder_name in enumerate(folder_names):
            if folder_name == folder_to_rm:
                folder = ''.join([f'/{f}' for f in folder_names[:i]])
                break
        if folder not in new_folders:
            new_folders.append(folder)
    return new_folders


def test_examples():
    assert remove_folder(
        ['/a', '/a/b', '/c/d', '/c/d/e', '/c/f', '/c/f/g'], 'c'
    ) == ['/a', '/a/b']

    assert remove_folder(
            ['/a', '/a/b', '/c/d', '/c/d/e', '/c/f', '/c/f/g'], 'd'
    ) == ['/a', '/a/b', '/c', '/c/f', '/c/f/g']


def test_folder_in_the_end():
    assert remove_folder(['/a/b/c', '/c/d', '/d/c'], 'd') == ['/a/b/c', '/c']


def test_folder_not_found():
    assert remove_folder(['/a/b/c', '/d/e/f'], 'g') == ['/a/b/c', '/d/e/f']


if __name__ == '__main__':
    test_examples()
    test_folder_in_the_end()
    test_folder_not_found()