fixed issue where permits were still valid after being used
fixed issue where permits were still valid after being used

chenclee/utacm_icpc_autojudge,ilinum/utacm_icpc_autojudge,chenclee/utacm_icpc_autojudge,chenclee/utacm_icpc_autojudge,chenclee/utacm_icpc_autojudge,ilinum/utacm_icpc_autojudge,ilinum/utacm_icpc_autojudge,ilinum/utacm_icpc_autojudge,ilinum/utacm_icpc_autojudge,ilinum/utacm_icpc_autojudge,chenclee/utacm_icpc_autojudge,chenclee/utacm_icpc_autojudge