/in/foo.cc: In function 'int main()':
/in/foo.cc:18:15: error: expected ':' before 'if'
   18 |         case 2
      |               ^
      |               :
   19 |             if ((year % 4 == 0 && year % 100 != 0) || (year % 400 == 0)) {
      |             ~~