0分求助

#include<bits/stdc++.h>
using namespace std;
bool runnian(int x) {
	if(x%4==0&&x%100!=0)
		return 1;
	else if(x%400==0) {
		return 1;
	}
	return 0;
}
int main() {
	int a,b;
	cin>>a>>b;
	if(b==2&&runnian(a)==1||b==4||b==6||b==9||b==11)
		cout<<"30";
	else if(b==2&&runnian(a)==0)
	cout<<"29";
	else
	cout<<"31";
		return 0;
}