/in/foo.cc: In function 'int main()':
/in/foo.cc:10:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for (int i = 0; i < isbn.size()-1; i++) {
                    ^
/in/foo.cc:12:7: error: conflicting declaration 'int num'
   int num = 0;
       ^
/in/foo.cc:11:8: note: previous declaration as 'char num'
   char num = isbn[i];
        ^
/in/foo.cc:13:7: error: 'tmp' was not declared in this scope
   if (tmp != '-') {
       ^
/in/foo.cc:18:2: error: 'check' was not declared in this scope
  check = sum % 11;
  ^
/in/foo.cc:31:1: error: expected '}' at end of input
 }
 ^