ngay

#include<iostream>
using namespace std;
bool Namnhuan(int nam) {
	if ((nam % 4 == 0) && (nam % 100 != 0)) {
		return 1;
	}
	else {
		if (nam % 400 == 0) {
			return 1;
		}
		else {
			return 0;
		}
	}
}
int  Ngay(int thang, int nam) {


		switch (thang)
		{
		case 1:
		case 3:
		case 5:
		case 7:
		case 8:
		case 10:
		case 12:
			cout << "31";
			break;
		case 4:
		case 6:
		case 9:
		case 11:
			cout << "30";
			break;
		case 2:
			if (Namnhuan(nam) == 1) {
				cout << "29";
			}
			else{
				cout << "28";
				break;
		}
		default: if ((thang < 0) || (thang > 12)) {
			cout << "khong ton tai";
		}


	}
		return 0;
}
int  main(){
	int thang, nam;
	cout << " nhap thang , nam :";
	cin >> thang >> nam;
	return Ngay(thang, nam);
	system("pause");

}