Java第四周练习+作业
一.练习:
1.输入一个年份,判断是不是闰年(能被4整除但不能被100整除,或者能被400整除)
package com.ym.pc; import java.util.Scanner; public class Practice1 { /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub Scanner input = new Scanner(System.in); System.out.println("输入一个年份"); int year = input.nextInt(); if (year % 4 == 0 && year % 100 != 0 || year % 400 == 0) { System.out.println("该年份是闰年"); } else { System.out.println("该年份是平年"); } } }
2.输入一个4位会员卡号,如果百位数字是随机数,就输出是幸运会员,否则就输出不是
package com.ym.pc; import java.util.Random; import java.util.Scanner; public class Practise2 { /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub Scanner input = new Scanner(System.in); System.out.println("输入一个4位会员卡号"); int number = input.nextInt(); int baiwei = number / 100 % 10; Random r = new Random(); int a = (int) r.nextInt(10); if (baiwei == a) { System.out.println("该用户是幸运会员"); } else { System.out.println("该用户不是幸运会员"); } } }
3.已知函数,输入x的值,输出对应的y的值.
x + 3 ( x > 0 )
y = 0 ( x = 0 )
x*2 –1 ( x < 0 )
package com.ym.pc; import java.util.Scanner; public class Practise3 { /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub Scanner input = new Scanner(System.in); System.out.println("输入x的值"); int x = input.nextInt(); int y; if (x > 0) { y = x + 3; } else if (x == 0) { y = 0; } else { y = x * 2 - 1; } System.out.println("y的值是" + y); } }
4.输入三个数,判断能否构成三角形(任意两边之和大于第三边).
package com.ym.pc; import java.util.Scanner; public class Practise { /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub Scanner input = new Scanner(System.in); System.out.println("输入三个数"); int x = input.nextInt(); int y = input.nextInt(); int z = input.nextInt(); if (x + y > z && x + z > y && y + z > x) { System.out.println("可以构成三角形"); } else { System.out.println("不能构成三角形"); } } }
二.作业
1.输入年份月份,输出该月的天数(闰年2月29天,条件参考上机练习1).
package com.ym.ho; import java.util.Scanner; public class HomeWork1 { /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub Scanner input = new Scanner(System.in); System.out.println("输入年份月份"); int year = input.nextInt(); int month = input.nextInt(); if (month == 1 || month == 3 || month == 5 || month == 7 || month == 8 || month == 10 || month == 12) { System.out.println("该月有31天"); } else if (month == 4 || month == 6 || month == 9 || month == 11) { System.out.println("该月有30天"); } else if (year % 2 == 0 && year % 100 != 0 || year % 400 == 0) { System.out.println("该月有29天"); } else { System.out.println("该月有28天"); } } }
2.给定一个成绩a,使用switch结构求出a的等级
A:90-100,B:80-89,C:70-79,D:60-69,E:0~59
package com.ym.ho; import java.util.Scanner; public class HomeWork2 { /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub Scanner input = new Scanner(System.in); System.out.println("输入一个成绩"); int a = input.nextInt(); switch (a / 10) { case 9: case 10: System.out.println("A"); break; case 8: System.out.println("B"); break; case 7: System.out.println("C"); break; case 6: System.out.println("D"); break; default: System.out.println("E"); } } }
3.输入一个数字,判断是一个奇数还是偶数.
package com.ym.ho; import java.util.Scanner; public class HomeWork3 { /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub Scanner input = new Scanner(System.in); System.out.println("请输入一个数字"); int m = input.nextInt(); if (m % 2 == 0) { System.out.println("该数是一个偶数"); } else if (m%2!=0){ System.out.println("该数是一个奇数"); } else{ System.out.println("该数既不是奇数也不是偶数"); } } }
4.编写程序,判断一个变量x的值,如果是1,输出x=1,如果是5,输出x=5,如果是10,输出x=10,除了以上几个值,都输出x=none.
package com.ym.ho; import java.util.Scanner; public class HomeWork4 { /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub Scanner input = new Scanner(System.in); System.out.println("输入x的值"); int x = input.nextInt(); if (x == 1) { System.out.println("x=1"); } else if (x == 5) { System.out.println("x=5"); } else if (x == 10) { System.out.println("x=10"); } else { System.out.println("x=none"); } } }
5.判断一个数字是否能被5和6同时整除(打印能被5和6整除),或只能被5整除(打印能被5整除),或只能被6整除(打印能被6整除),不能被5或6整除(打印不能被5或6整除).
package com.ym.ho; import java.util.Scanner; public class HomeWork5 { /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub Scanner input = new Scanner(System.in); System.out.println("随机输入一个数字"); int x = input.nextInt(); if (x % 5 == 0 && x % 6 == 0) { System.out.println("该数能被5和6整除"); } else if (x % 5 == 0) { System.out.println("该数能被5整除"); } else if (x % 6 == 0) { System.out.println("该数能被6整除"); } else if (x % 5 != 0 || x % 6 != 0) { System.out.println("该数不能被5或6整除"); } else { System.out.println("错误"); } } }