/in/foo.cc: In function 'int main()':
/in/foo.cc:8:13: error: unable to find string literal operator 'operator""a' with 'const char [2]', 'long unsigned int' arguments
  cout<<"4"<<"2"a<<endl;
             ^~~~
/in/foo.cc:6:6: warning: unused variable 'a' [-Wunused-variable]
  int a;
      ^
/in/foo.cc:7:8: warning: unused variable 's' [-Wunused-variable]
  short s;
        ^