foo.cc: In function 'int main()':
foo.cc:39:17: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     int t; scanf("%d", &t);
            ~~~~~^~~~~~~~~~
foo.cc:45:37: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         for(int i=1;i<=24;i++) scanf("%d", &r[i]);
                                ~~~~~^~~~~~~~~~~~~
foo.cc:46:21: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         int n; scanf("%d", &n);
                ~~~~~^~~~~~~~~~
foo.cc:50:28: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
             int hour; scanf("%d", &hour);
                       ~~~~~^~~~~~~~~~~~~
foo.cc:75:9: warning: 'ret' may be used uninitialized in this function [-Wmaybe-uninitialized]
         if(!ret) {
         ^~

自豪的采用HydroJudge(https://github.com/hydro-dev/Hydro)进行评测。