Java_实例_作业(控制台学生管理系统)

import java.util.Arrays;
import java.util.Scanner;

public class StudentScore {
    static Scanner input = new Scanner(System.in);\
    //学生个数
    static String names[] = new String[2];
    //课程数量
    static int score[][] = new int[names.length][5];
    private static Scanner scan;
    /**
     * names[]长度
     */
    static int LEN = names.length;
    /**
     * score[]长度
     */
    static int SLEN = score.length;

    public static void main(String args[]) {
        welcome();
        options();

    }

    public static void welcome() {
        System.out.println("请输入一个选项:");
        System.out.print("1`输入学生成绩    ");
        System.out.print("2`显示全部学生成绩        ");
        System.out.println("3`查询学生成绩");
        System.out.print("4`求学生总分     ");
        System.out.print("5`显示最高分       ");
        System.out.println("6`显示最低分");
        System.out.print("7`查看平均分     ");
        System.out.println("8`退出系统");
    }

    public static void options() {
        System.out.println("请输入您所需查询的选项：");

        int num = input.nextInt();
        switch (num) {
        case 1:
            entryResults();
            welcome();
            options();
            break;
        case 2:
            studentInfo();
            options();
            break;
        case 3:
            inquireInfo();
            welcome();
            options();
            break;
        case 4:
            totalScore();
            welcome();
            options();
            break;
        case 5:
            maxScore();
            welcome();
            options();
            break;
        case 6:
            minScore();
            welcome();
            options();
            break;
        case 7:
            avgScore();
            welcome();
            options();
            break;
        case 8:
            System.out.println("bye!");
            System.exit(0);
            break;
        default:
            System.out.println("输入有误，请重新输入：");
            welcome();
            options();
        }
    }

    public static void entryResults() {
        for (int i = 0; i < LEN; i++) {
            System.out.println("请输入第" + (i + 1) + "个学生姓名");
            names[i] = input.next();
        }
        for (int i = 0; i < SLEN; i++) {
            for (int j = 0; j < score[i].length; j++) {
                System.out.println("请录入" + names[i] + "的" + getCoursName(j) + "成绩");
                score[i][j] = input.nextInt();
            }
        }
        System.out.println("录入完成！");
    }

    public static String getCoursName(int i) {
        switch (i) {
        case 0:
            return "数学";
        case 1:
            return "英语";
        case 2:
            return "计算机";
        case 3:
            return "体育";
        case 4:
            return "语文";
        default:
            return "无";

        }
    }

    public static void studentInfo() {
        System.out.println("显示所有学生信息：");
        System.out.println("姓名\t数学\t英语\t计算机\t体育\t语文");
        for (int i = 0; i < LEN; i++) {
            System.out.println(names[i] + "\t");
            for (int j = 0; j < score[i].length; j++) {
                System.out.println(score[i][j] + "\t");
            }
        }
    }

    public static void inquireInfo() {
        System.out.println("请输入要查询的学生姓名:");
        scan = new Scanner(System.in);
        String name = scan.next();
        for (int i = 0; i < LEN; i++) {
            if (name.equals(names[i])) {
                for (int j = 0; j < 5; j++) {
                    System.out.println(names[i] + "的 " + getCoursName(j) + "成绩是: " + score[i][j]);
                }
            }
        }
    }

    public static void totalScore() {
        int[] sum = new int[5];
        for (int i = 0; i < LEN; i++) {
            for (int j = 0; j < 5; j++) {
                sum[j] += score[i][j];
            }
        }
        for (int i = 0; i < 5; i++) {
            System.out.println(getCoursName(i) + "总成绩是: " + sum[i]);
        }
    }

    public static void maxScore() {
        for (int i = 0; i < SLEN; i++) {
            Arrays.sort(score[i]);
            System.out.println(names[i] + "最高分是 : " + score[i][score[i].length - 1]);
        }
    }

    public static void minScore() {
        for (int i = 0; i < SLEN; i++) {
            Arrays.sort(score[i]);
            System.out.println(names[i] + "最低分是 : " + score[i][0]);
        }
    }

    public static void avgScore() {
        int[] nums = new int[LEN];
        for (int i = 0; i < SLEN; i++) {
            for (int j = 0; j < score[i].length; j++) {
                nums[i] += score[i][j];
            }
        }
        for (int j = 0; j < LEN; j++) {
            System.out.println(names[j] + "平均分是 : " + (nums[j] / score[j].length));
        }

    }
}