/in/foo.cc: In function 'int kto10(int, std::__cxx11::string)':
/in/foo.cc:7:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0;i<s.size();i++){
              ~^~~~~~~~~
/in/foo.cc: In function 'std::__cxx11::string _10tok(int, int)':
/in/foo.cc:20:3: warning: this 'else' clause does not guard... [-Wmisleading-indentation]
   else
   ^~~~
/in/foo.cc:22:4: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'else'
    n/=k;
    ^