20171123 使用陣列參考解答 & 20171207 多重 for 迴圈時鐘範例

20171123_array.cpp

#include <iostream>
using namespace std;

int main()
{
    int students, total = 0;
  
    cout << "班級人數：";
    cin >> students;
    
    int score[students];
    for (int i = 0; i < students; i++) {
        cout << i + 1 << " 號同學的成績：";
        cin >> score[i];
    }
    
    
    for (int i = 0; i < students; i++) {
        total += score[i];
    }
    
    cout << "全班總分是：" << total;
    cout << "全班平均是：" << total/students;
    
    
    // ===== 查詢學生成績 ===== //
    
    int studentNo;
    while (true) {
        cout << "查詢座號：";
        cin >> studentNo;
        
        // 超過座號範圍就終止程式
        if (studentNo < 1 || studentNo > students) {  // 想想看為什麼 students 不用 +1？
            break;
        }
        
        cout << i + 1 << "號同學的成績是 " << score[studentNo] << "分" << endl;
    }
   
    cout << "程式結束 掰掰";
    
    return 0;
}

20171207_clock.cpp

#include <iostream>
using namespace std;

int main()
{
    for (int hour = 0; hour <= 23; hour++) {
        for (int minute = 0; minute <= 59; minute++) {
            for (int second = 0; second <= 59; second++) {
                // 未達兩位數時補 0
                if (hour < 10) {
                    cout << "0";
                }
                cout << hour << ":";
                
                if (minute < 10) {
                    cout << "0";
                }
                cout << minute << ":";
                
                if (second < 10) {
                    cout << "0";
                }
                cout << second << endl; // 最後顯示完秒數後換行
            }
        }
    }
    
    return 0;
}