foo.cc: In function ‘int main()’:
foo.cc:7:29: error: expected ‘;’ before ‘return’
    7 |         cout<<"1"<<"1"<<endl
      |                             ^
      |                             ;
    8 |         return 0;
      |         ~~~~~~               
foo.cc:5:14: warning: unused variable ‘a’ [-Wunused-variable]
    5 |         bool a;
      |              ^
foo.cc:6:14: warning: unused variable ‘v’ [-Wunused-variable]
    6 |         char v;
      |              ^