foo.cc: In function ‘int main()’:
foo.cc:25:9: error: ‘i’ was not declared in this scope
   25 |     for(i=1;i<=1005;i++)
      |         ^
foo.cc:29:18: warning: comparison of integer expressions of different signedness: ‘int’ and ‘std::vector<int>::size_type’ {aka ‘long unsigned int’} [-Wsign-compare]
   29 |     for(int i=0;i<g[mx].size();i++)
      |                 ~^~~~~~~~~~~~~