foo.cc:1:33: error: 'gapday' does not name a type
    1 |                                 gapday += 365;
      |                                 ^~~~~~
foo.cc:2:9: error: expected declaration before '}' token
    2 |         }
      |         ^
foo.cc:3:9: error: expected unqualified-id before 'return'
    3 |         return gapday;
      |         ^~~~~~
foo.cc:4:1: error: expected declaration before '}' token
    4 | }
      | ^
foo.cc: In function 'int month(int, int)':
foo.cc:8:14: warning: statement has no effect [-Wunused-value]
    8 |         for (month1; month1 < month2; month1++)
      |              ^~~~~~
foo.cc: In function 'int main()':
foo.cc:37:9: error: 'cin' was not declared in this scope
   37 |         cin >> year1 >> month1 >> day1;
      |         ^~~
foo.cc:39:9: error: 'cout' was not declared in this scope
   39 |         cout << year(year1, year2) <<" " << month(month1, month2) <<" " << day(day1, day2);
      |         ^~~~
foo.cc:39:17: error: 'year' was not declared in this scope; did you mean 'year2'?
   39 |         cout << year(year1, year2) <<" " << month(month1, month2) <<" " << day(day1, day2);
      |                 ^~~~
      |                 year2

[Hydro](https://hydro.ac)提供评测服务