foo.cc: In function 'int printMonth(int, int)':
foo.cc:26:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^
foo.cc: In function 'int IsLeapYear(int)':
foo.cc:29:29: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
    if(year%400==0||year%4==0&&year%100!=0)
                    ~~~~~~~~~^~~~~~~~~~~~~
foo.cc: In function 'int main()':
foo.cc:79:19: warning: unused variable 'd' [-Wunused-variable]
    int year,month,d;
                   ^

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