元旦作业 1~6题

package cn.yang.qian.qian;



import java.util.Scanner;



public class average1 {

	public static void main(String[] args) {

		// 第一题 计算平均分

		Scanner input = new Scanner(System.in);

		System.out.println("请输入语文成绩");

		double Chinese = input.nextDouble();

		System.out.println("请输入数学成绩");

		double Math = input.nextDouble();

		System.out.println("请输入英语成绩");

		double English = input.nextDouble();



		double sum = Chinese + Math + English;

		double average = sum / 3;

		System.out.println("总成绩是:" + sum);

		System.out.println("平均分是:" + average);

	}

}



package cn.yang.qian.qian;



public class shopping2 {

	public static void main(String[] args) {

		// 第二题 购物清单

		int bagPrice = 198;

		int badmintonPrice = 90;

		int battledorePrice = 400;

		System.out.println("********** 购 物 清 单 **********");

		System.out.println("商品名称" + "\t" + "单价" + "\t" + "数量" + "\t" + "总价");

		System.out.println("登山包" + "\t" + "￥" + bagPrice + "\t" + "1" + "\t"

				+ "￥" + bagPrice * 1);

		System.out.println("羽毛球" + "\t" + "￥" + badmintonPrice + "\t" + "3"

				+ "\t" + "￥" + badmintonPrice * 3);

		System.out.println("羽毛球拍" + "\t" + "￥" + battledorePrice + "\t" + "1"

				+ "\t" + "￥" + battledorePrice * 1);

		System.out.println("==============================");

		int sum = bagPrice * 1 + badmintonPrice * 3 + battledorePrice * 1;

		int money = 8888;

		int change = money - sum;

		System.out.println("应付金额:" + sum + "元");

		System.out.println("实收金额:" + money + "元");

		System.out.println("找零:" + change + "元");



	}

}





package cn.yang.qian.qian;



import java.util.Scanner;



public class performance3 {

	public static void main(String[] args) {

		// 第三题 接收成绩 分等级

		double student[] = new double[10];

		double sum = 0;// 总成绩

		double score = 0;// 平均分

		Scanner input = new Scanner(System.in);

		for (int i = 0; i < student.length; i++) {

			System.out.println("请输入第" + (i + 1) + "名学生的成绩");

			student[i] = input.nextDouble();

			if (student[i] > 100 || student[i] < 1) {

				System.out.println("输入成绩无效");

				break;

			}

			sum = sum + student[i];

			score = sum / 10;

		}

		if (score >= 1) {

			int a = (int) score / 10;

			switch (a) {

			case 10:

			case 9:

				System.out.println("该班级学员等级为A");

				break;

			case 8:

				System.out.println("该班级学员等级为B");

				break;

			case 7:

				System.out.println("该班级学员等级为C");

				break;

			case 6:

				System.out.println("该班级学员等级为D");

				break;

			case 5:

			case 4:

			case 3:

			case 2:

			case 1:

			case 0:

				System.out.println("该班级学员等级为E");

				break;

			}

		}

	}

}





package cn.yang.qian.qian;



public class test4 {

	public static void main(String[] args) {

		// 第四题 输出1~1000之间5的倍数 并统计个数

		int conut = 0;

		System.out.println("1~1000之间5的倍数为:");

		for (int i = 1; i <= 1000; i++) {

			if (i % 5 != 0) {

				continue;

			} else {

				conut++;

				if (conut % 8 == 0) {

					System.out.println(i);

				} else {

					System.out.print(i + "\t");

				}



			}

		}

		System.out.println("1~1000之间5个倍数一共有" + conut + "个");

	}

}





package cn.yang.qian.qian;



import java.util.Arrays;

import java.util.Scanner;



public class test5 {

	public static void main(String[] args) {

		// 第五题 录入成绩 按降序排列

		int student[] = new int[10];

		int a = 0;

		int b = 0;

		int c = 0;

		Scanner input = new Scanner(System.in);

		System.out.println("学员成绩统计表");

		for (int i = 0; i < student.length; i++) {

			System.out.println("请输入第" + (i + 1) + "个学员的成绩");

			student[i] = input.nextInt();

		}

		System.out.println("********************************");

		System.out.println("降序输出所有成绩为:");

		Arrays.sort(student);// 排序

		for (int i = student.length - 1; i >= 0; i--) {

			System.out.print(student[i] + " ");

			if (student[i] >= 80 && student[i] <= 100) {

				a++;

			}

			if (student[i] >= 60 && student[i] < 80) {

				b++;

			}

			if (student[i] < 60) {

				c++;

			}

		}

		System.out.println("\t");

		System.out.println("********************************");

		System.out.println("其中:");

		System.out.println("100分--80分的学员有:" + a + "个");

		System.out.println("79分--60分的学员有:" + b + "个");

		System.out.println("60分以下的学员有:" + c + "个");

	}

}





package cn.yang.qian.qian;



import java.util.Arrays;

import java.util.Scanner;



public class test6 {

	public static void main(String[] args) {

		// 输入数据 判断是否存在数组中

		int qianqian[] = new int[5];

		Scanner input = new Scanner(System.in);

		for (int i = 0; i < qianqian.length; i++) {

			System.out.println("请输入第" + (i + 1) + "个数字");

			qianqian[i] = input.nextInt();

		}

		System.out.print("所接受的数字为:[");

		for (int qian : qianqian) {

			System.out.print(qian + ",");

		}

		System.out.println("]");

		System.out.println("请输入查询数字");

		int number = input.nextInt();

		int count = Arrays.binarySearch(qianqian, number);

		if (count == -1) {

			System.out.println("该数字不存在与本数组中");

		} else {

			System.out.println("该数字是本数组中第:" + (count + 1) + "个成员");

		}

		String str = Arrays.toString(Arrays.copyOf(qianqian, number));

		if (count == 0) {

			System.out.println("该数字前无数据");

		} else {

			System.out.println("该数字前的数组内容为:" + str);

		}

	}

}