---
tags: Cmoney_Java題目
---
Java_Cmoney_st208
===


1.需要的 function 和 Class
---
1.1 學生 Class 包含他的座號和缺席紀錄
---
因為是在答題系統哩，Class 建立到同一個.java 裡，不用 public
1. 2個屬性(seat absence),1個方法(print:印"座號.缺席次數")
2. 為方便不用 getter

class Stu {
    int seat;
    int absence;

    Stu(int seat, int absence) {
        this.seat = seat;
        this.absence = absence;
    }

    void print() {
        System.out.println(this.seat + "." + this.absence);
    }
}

1.2 使用座號，從學生陣列中取得該學生物件
---

public static Stu getStu(Stu[] stus, int seat) {
        for (int i = 0; i < 10; i++) {
            if (stus[i].seat == seat)
                return stus[i];
        }
        return null;
    }

2.主程式
---
1. 創建有10個學生物件的陣列
2. 利用迴圈，實體那10個學生
3. 迴圈，連續輸入5天的缺席狀況，int n 代表有幾筆缺席紀錄
如果是-1代表沒有缺席紀錄，用`continue;`跳到下一天
4. 迴圈，連續讀取 n 個缺席學生座號，利用讀取到座號，
使用 getStu(stus,seat)，然後直接操作實體屬性(缺席)++
5. 最後用迴圈印出所有學生的資料

public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        Stu[] stus = new Stu[10];
        for (int i = 0; i < 10; i++) {
            stus[i] = new Stu(i + 1, 0);
        }
        for (int i = 0; i < 5; i++) {
            int n = sc.nextInt();
            if (n == -1)
                continue;
            for (int j = 0; j < n; j++) {
                getStu(stus, sc.nextInt()).absence++;
            }
        }
        for (int i = 0; i < 10; i++) {
            stus[i].print();
        }
    }

3.完整程式
---

import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        Stu[] stus = new Stu[10];
        for (int i = 0; i < 10; i++) {
            stus[i] = new Stu(i + 1, 0);
        }
        for (int i = 0; i < 5; i++) {
            int n = sc.nextInt();
            if (n == -1)
                continue;
            for (int j = 0; j < n; j++) {
                getStu(stus, sc.nextInt()).absence++;
            }
        }
        for (int i = 0; i < 10; i++) {
            stus[i].print();
        }
    }

    public static Stu getStu(Stu[] stus, int seat) {
        for (int i = 0; i < 10; i++) {
            if (stus[i].seat == seat)
                return stus[i];
        }
        return null;
    }


}

class Stu {
    int seat;
    int absence;

    Stu(int seat, int absence) {
        this.seat = seat;
        this.absence = absence;
    }

    void print() {
        System.out.println(this.seat + "." + this.absence);
    }

}