foo.cc: In function ‘int main()’:
foo.cc:6:17: error: ‘b’ was not declared in this scope
    6 |         cin>>a>>b;
      |                 ^
foo.cc:15:29: error: expected ‘;’ before ‘}’ token
   15 |                 }while(a!=0)
      |                             ^
      |                             ;
   16 |         }
      |         ~