foo.cc: In function 'int main()':
foo.cc:7:2: error: 'cou' was not declared in this scope
  cou<<3;
  ^~~
foo.cc:9:2: error: 'cou' was not declared in this scope
  cou<<4;
  ^~~
foo.cc:11:2: error: 'cou' was not declared in this scope
  cou<<6;
  ^~~
foo.cc:13:2: error: 'cou' was not declared in this scope
  cou<<5;
  ^~~
foo.cc:15:2: error: 'cou' was not declared in this scope
  cou<<7;
  ^~~
foo.cc:17:2: error: 'cou' was not declared in this scope
  cou<<8;
  ^~~
foo.cc:19:2: error: 'cou' was not declared in this scope
  cou<<9;
  ^~~
foo.cc:21:2: error: 'cou' was not declared in this scope
  cou<<10;
  ^~~
foo.cc:23:2: error: 'cou' was not declared in this scope
  cou<<11;
  ^~~