/in/foo.cc: In function 'bool judge(std::vector<int>)':
/in/foo.cc:7:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i1 = 0; i1 < (num.size() + 1) / 2; i1++)
                     ~~~^~~~~~~~~~~~~~~~~~~~~~
/in/foo.cc: In function 'std::vector<int> i(std::vector<int>)':
/in/foo.cc:19:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i1 = 0; i1 < num.size(); i1++)
                     ~~~^~~~~~~~~~~~
/in/foo.cc: In function 'int main()':
/in/foo.cc:52:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for(int i1 = 0; i1 < m.size(); i1++)
                         ~~~^~~~~~~~~~