java第四次作业

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 homework;

import java.util.Scanner;

public class test16 {
	public static void main(String[] args) {
		Scanner s = new Scanner(System.in);
		System.out.println("输入一个年份");
		int n = s.nextInt();
		if ((n % 4 == 0 && n % 100 != 0) || n % 400 == 0) {
			System.out.println("闰年");
		} else {
			System.out.println("不是闰年");
		}
	}
}

  

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 homework;

import java.util.Random;
import java.util.Scanner;

public class tets17 {
	 public static void main(String[] args) {
	        Scanner sc = new Scanner(System.in);
	        System.out.println("输入一个四位卡号");
	        int num = sc.nextInt();
	        if(num>9999||num<1000) {
	        	System.out.println("卡号错误");
	        }else {
	        	int target = num / 100 % 10;
		        Random r = new Random();
		        int n = r.nextInt(9);
		        System.out.println("幸运数字是:"+n);
		        if (target == n) {
		            System.out.println("恭喜成为幸运会员");
		        }
		        else {
		            System.out.println("很遗憾您未中奖");
		        }
	        }
	        
	        
	 }
}

  

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 homework;

import java.util.Scanner;

public class tets18 {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		System.out.println("输入一个数x");
		int x =sc.nextInt();
		int y ;
		if(x>0) {
			y=x+3;
			System.out.println("y=" + y);
		}else if(x==0) {
			y = 0;
			System.out.println("y=" + y);
		}else if(x<0) {
			y = x*2-1;
			System.out.println("y=" + 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 homework;

import java.util.Scanner;

public class tets19 {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		System.out.println("输入三个大于0的整数");
		int a = sc.nextInt();
		int b = sc.nextInt();
		int c = sc.nextInt();
		if (a + b > c && a + c > b && b + c > a) {
			System.out.println("可以构成三角形");
		} else {
			System.out.println("不可以构成三角形");
		}
	}
}

  

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 homework;

import java.util.Scanner;

public class test20 {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		System.out.println("输入年份月份");
		int year = sc.nextInt();
		int month = sc.nextInt();
		if ((year % 4 == 0 && year % 100 != 0) || (year % 400 == 0)) {
			if (month == 2) {
				System.out.println(29);
			}
		} else {
			if (month == 2) {
				System.out.println(28);
			}
		}
		if (month == 1 || month == 3 || month == 5 || month == 7 || month == 8 || month == 10 || month == 12) {
			System.out.println(31);
		} else if (month == 4 || month == 6 || month == 9 || month == 11) {
			System.out.println(3);
		}

	}
}

  

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 homework;

import java.util.Scanner;

public class tets21 {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		System.out.println("输入成绩");
		int course = sc.nextInt();
		if (course < 0) {
			System.out.println("输入的成绩有误");
		}
		int n = course / 10;
		switch (n) {
		case 9:
			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;
		case 5:
			System.out.println("E");
		}
	}
}

  

3.输入一个数字,判断是一个奇数还是偶数

package homework;

import java.util.Scanner;

public class test22 {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		System.out.println("输入一个数");
		int num = sc.nextInt();
		if (num % 2 == 0) {
			System.out.println("偶数");
		} else {
			System.out.println("奇数");
		}

	}
}

  

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 homework;

import java.util.Scanner;

public class tets23 {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		System.out.println("输入一个数x");
		int x = sc.nextInt();
		if (x == 1) {
			System.out.println("x = " + x);
		} else if (x == 5) {
			System.out.println("x = " + x);

		} else if (x == 10) {
			System.out.println("x = " + x);

		} 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 homework;

import java.util.Scanner;

public class test24 {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		System.out.println("输入一个数");
		int num = sc.nextInt();
		if ((num % 5 == 0) && (num % 6 == 0)) {
			System.out.println("能被5和6整除");
		} else if (num % 5 == 0) {
			System.out.println("能被5整除");
		} else if (num % 6 == 0) {
			System.out.println("能被6整除");
		} else {
			System.out.println("不能被5和6整除");
		}
	}
}

  

posted on 2021-03-29 14:57  chenyulin11  阅读(19)  评论(0编辑  收藏  举报

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