/in/foo.cc:5:7: error: expected ')' before ';' token
  int a;
       ^
/in/foo.cc:4:5: warning: 'int main(int)' takes only zero or two arguments [-Wmain]
 int main(
     ^~~~
/in/foo.cc:9:8: error: expected constructor, destructor, or type conversion before '(' token
  printf("输入变量的值，并用逗号隔开。\n");//提示输入并换行
        ^
/in/foo.cc:10:1: error: expected unqualified-id before numeric constant
 2
 ^
/in/foo.cc:13:8: error: expected constructor, destructor, or type conversion before '(' token
  printf("%8s\n",s);
        ^
/in/foo.cc:15:2: error: expected unqualified-id before 'return'
  return 0;
  ^~~~~~
/in/foo.cc:16:1: error: expected declaration before '}' token
 }
 ^