foo.cc: In function ‘int main()’:
foo.cc:9:22: warning: comparison of integer expressions of different signedness: ‘int’ and ‘std::__cxx11::basic_string<char>::size_type’ {aka ‘long unsigned int’} [-Wsign-compare]
    9 |         for(int i=0;i<m.size();i++)
      |                     ~^~~~~~~~~
foo.cc:43:45: warning: iteration 30 invokes undefined behavior [-Waggressive-loop-optimizations]
   43 |                                 cout<<n[i][j];
      |                                       ~~~~~~^
foo.cc:42:38: note: within this loop
   42 |                         for(int j=0;j<105;j++)
      |                                     ~^~~~