foo.cc: In function 'int main()':
foo.cc:24:30: warning: self-comparison always evaluates to false [-Wtautological-compare]
                 if(sta&(1<<j)!=(1<<j)) continue;
                        ~~~~~~^~~~~~~~
foo.cc:24:30: warning: suggest parentheses around comparison in operand of '&' [-Wparentheses]
foo.cc:8:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d",&n);
     ~~~~~^~~~~~~~~
foo.cc:11:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
             scanf("%d",&a[i][j]);
             ~~~~~^~~~~~~~~~~~~~~

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

{"receive":"2020-07-30T14:03:49.534Z","handle":"2020-07-30T14:03:49.534Z","cache_start":"2020-07-30T14:03:49.541Z","read_cases":"2020-07-30T14:03:49.671Z","judge":"2020-07-30T14:03:49.672Z","done":"2020-07-30T14:03:51.067Z"}