/in/foo.cc: In function 'int main()':
/in/foo.cc:14:33: warning: 'n' may be used uninitialized in this function [-Wmaybe-uninitialized]
  cout<<x<<" "<<y<<" "<<m<<" "<<n;
                                 ^
/in/foo.cc:14:27: warning: 'm' may be used uninitialized in this function [-Wmaybe-uninitialized]
  cout<<x<<" "<<y<<" "<<m<<" "<<n;
                           ^~~