/in/foo.cc: In member function 'int Date::leap()':
/in/foo.cc:10:47: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
         if ((year % 400 == 0 || year % 4 == 0 && year % 100 != 0) && month == 2)
                                 ~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~
/in/foo.cc: In function 'int main()':
/in/foo.cc:32:9: warning: unused variable 'n' [-Wunused-variable]
     int n, i;
         ^
/in/foo.cc:32:12: warning: unused variable 'i' [-Wunused-variable]
     int n, i;
            ^