1、先存平年的每月天数 2、如果是闰年再修改即可

import java.util.Calendar;
import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner console = new Scanner(System.in);
        int year = console.nextInt();

        //write your code here......
        int[] month = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};  // 一年的月天数
        // 如果是闰年就特殊处理
        if ((year % 4 == 0 && year % 100 != 0) || year % 400 == 0) {
            month[1] = 29;
        }
        for (int i = 1; i <= month.length; i++) {
            System.out.println(year + "年" + i + "月:" + month[i-1] + "天");
        }

    }
}