ThangNam.java

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 */
package btvn3;

import javax.swing.JOptionPane;

/**
 *
 * @author Kawaii
 */
public class ThangNam {

    public static void main(String[] args) {
        JOptionPane.showMessageDialog(null, "Pham Tuan Sang - 20146596");
        String strThang, strNam;
        int thang, nam;
        int thang2;
        do {
            strThang = JOptionPane.showInputDialog(null, "Nhap thang: ");
            thang = Integer.parseInt(strThang);
        } while (thang < 1 || thang > 12);

        do {
            strNam = JOptionPane.showInputDialog(null, "Nhap nam: ");
            nam = Integer.parseInt(strNam);
        } while (nam < 0);

        if (nam % 4 == 0) {
            if (nam % 100 == 0 && nam % 400 != 0) {
                thang2 = 28;
            } else {
                thang2 = 29;
            }
        } else {
            thang2 = 28;
        }
        switch (thang) {
            case 1:
            case 3:
            case 5:
            case 7:
            case 8:
            case 10:
            case 12:
                JOptionPane.showMessageDialog(null, "Thang nay co 31 ngay");
                break;
            case 4:
            case 6:
            case 9:
            case 11:
                JOptionPane.showMessageDialog(null, "Thang nay co 30 ngay");
                break;
            case 2:
                JOptionPane.showMessageDialog(null, "Thang nay co " + thang2 + " ngay");
                break;
        }

    }
}