java闰年程序

闰年 public class RunNian public static void main String args int num 1 for int i 2000 i 3000 i if i 4 0 num if num 5 0 System out println import java util Scanner public class RunNian public static void main String args Scanner year new Scanner System in System out println 请输入年份 int y Integer parseInt year next if y 400 0 System out println 今年是闰年 else if y 4 0 else System out println 今年不是闰年 import java util Scanner import javax swing JOptionPane public class LeapYear public static void main String args String yearsString JOptionPane showInputDialog 输入年份输入年份 int year Integer parseInt yearsString if year 4 0 else JOptionPane showMessageDialog null 不是闰年不是闰年 水仙花数水仙花数 public class ShuiXianHuaShu1 public static void main String args int i j 0 int a 0 int b 0 int c 0 for i 100 i 1000 i a i 100 b i 10 10 c i 10 if i a a a b b b c c c System out println 水仙花数是 i j j 1 System out println 水仙花数的个数是 j 九九算法乘表九九算法乘表 public class MultiplicationList param args public static void main String args for int j 1 j 9 j for int i 1 i j i System out print i j i j System out println 水仙花数水仙花数 public class ShuiXianHuaShu1 public static void main String args int i j 0 int a 0 int b 0 int c 0 for i 100 i 1000 i a i 100 b i 10 10 c i 10 if i a a a b b b c c c System out println 水仙花数是 i j j 1 System out println 水仙花数的个数是 j 素数素数 import java util Scanner public static void main String args Scanner input new Scanner System in System out println 求多少以内的素数 int n input nextInt int i j first Loop for i 3 i n i for j 2 j i j if i j 0 continue first Loop System out println i 回文数 import java io public class PalindromeNumber public static void main String args int t 0 BufferedReader readStream new BufferedReader new InputStreamReader System in while true System out print 请输入整数 1 9999 try 异常处理 String p1 readStream readLine if p1 equals end System exit 0 t Integer parseInt p1 转换为整型 用来判断是否为整 型 catch IOException e System out println I O 操作出现异常 catch NumberFormatException e System out println 对不起 你输入的不是整数 请重新输入 continue break String str t StringBuffer p2 new StringBuffer str if p2 length 0 i s2 s0 i if s1 equals s2 JOptionPane showMessageDialog null 是回文串 Inane warning JOptionPane WARNING MESSAGE else JOptionPane showMessageDialog null 不是回文串 Inane warning JOptionPane WARNING MESSAGE public class Parents public void print System out println parents class Father extends Parents public void print System out println father class Mother extends Parents public void print System out println mother public class Test public void