/in/foo.cc: In function 'int main()':
/in/foo.cc:23:6: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  if(n<=m.size()){
     ~^~~~~~~~~~
/in/foo.cc:28:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  while(m.size()<n){
        ~~~~~~~~^~