def link_info_gen(C: dict, mapping: dict, link_delay, link_loss):   
    """Generate the specified link information 
    Args:
        C (dict): Capacity dictionary (key, value) = (link ID, capacity of the link).
        mapping (dict): Link dictionary (key, value) = (link ID, source and destination pair of the link).
        link_delay (float): Specified delay for the link.
        link_loss (float): Specified loss for the link.
    Returns:
        str: Link infomation for all specified links, seperated by ;.
    Examples:
        The return can be "link_info: s1, s17, 5, 5ms, 0, N/A, N/A; s2, s17, 5, 5ms, 0, N/A, N/A; ..."
    """
    
    link_info = "link_info: "
    for link_id, cap in C.items():
        link_info += "{}, {}, {}, {}ms, {}, N/A, N/A; ".format(*mapping[link_id], cap, link_delay, link_loss)
    return link_info[:-2]