foo.cc: In function 'std::vector<int> findLISS(std::vector<int>&)':
foo.cc:52:9: warning: variable 'max_size_index' set but not used [-Wunused-but-set-variable]
     int max_size_index = -1;
         ^~~~~~~~~~~~~~
foo.cc: In function 'int main()':
foo.cc:122:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d",&n);
     ~~~~~^~~~~~~~~
foo.cc:128:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
             scanf("%d",&put_in);
             ~~~~~^~~~~~~~~~~~~~

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