foo.cc: In function 'int main()':
foo.cc:8:17: error: 'days' was not declared in this scope
    8 |                 days=31;
      |                 ^~~~
foo.cc:9:66: error: expected primary-expression before ')' token
    9 |         else if( month==4 || month==6 || month==9 || month==11 ||)
      |                                                                  ^
foo.cc:10:17: error: 'days' was not declared in this scope
   10 |                 days=30;
      |                 ^~~~
foo.cc:13:38: error: expected primary-expression before '!=' token
   13 |                 if(year%4==0 && year%!=0 || year%400==0)
      |                                      ^~
foo.cc:14:25: error: 'days' was not declared in this scope
   14 |                         days=29;
      |                         ^~~~
foo.cc:17:17: error: 'days' was not declared in this scope
   17 |                 days=28;
      |                 ^~~~

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