Question

我正在为学校作业创建一个小程序，人们可以在其中输入自己的跑步历史（跑步里程，经过的时间），并查看他们潜在的10K速度和马拉松速度。显示速度后，将显示不同速度的表。

我有一个全局变量（pace），使用它运行的大多数计算都需要在for循环内更改，但不会为计算更新。

edit：我知道该程序的编写不佳，并且有很多内容可以压缩。但是，它可以工作并且将满足分配参数。在for循环中，循环的每次迭代都需要将变量“ pace”增加30。

public class MarathonTime {

public static void main(String[] args) {

    String name;
    double distance;
    int hours, minutes, seconds;
    double pace;

    @SuppressWarnings("resource")
    Scanner scanner = new Scanner(System.in);

    System.out.print("What is your first name? ");
    name = scanner.next();
    System.out.print("How many miles did you run today? ");
    distance = scanner.nextDouble();
    System.out.print("How long did it take? Hours: ");
    hours = scanner.nextInt();
    System.out.print("Minutes: ");
    minutes = scanner.nextInt();
    System.out.print("Seconds: ");
    seconds = scanner.nextInt();

    pace = ((hours * 3600) + (minutes * 60) + seconds) / distance;
    double marathonPace = pace * 26.2;
    double tenKPace = pace * 6.2;

    int paceMinutes, paceSeconds;
    paceMinutes = (int) pace / 60;
    paceSeconds = (int) pace % 60;

    int marathonHours, marathonMinutes, marathonSeconds;
    marathonHours = (int) marathonPace / 3600;
    marathonMinutes = (int) (marathonPace % 3600) / 60;
    marathonSeconds = (int) marathonPace % 60;

    int tenKMinutes, tenKSeconds;
    tenKMinutes = (int) tenKPace / 60;
    tenKSeconds = (int) tenKPace % 60;

    System.out.println("Hello " + name);
    System.out.print("Your pace is "); timeFormatPace(paceMinutes, paceSeconds);
    System.out.println();
    System.out.print("At this rate your marathon time would be ");  timeFormatMarathon(marathonHours, marathonMinutes, marathonSeconds); 
    System.out.println();
    System.out.print("and your 10K time would be "); timeFormat10K(tenKMinutes, tenKSeconds);
    System.out.println();
    System.out.println("Good luck with your training!");
    System.out.println();

     for(int i = 1; i <= 10; i++){
            if(i == 1) {
                System.out.println("Pace \t\t 10K Time \t\t Marathon Time");
                i++;
            }
            if(i == 2) {
                System.out.println("------------------------------------------------------");
                i++;
            }
            // input the tablePaces into the calcs and print them as the format
            pace = (281 + (i*30));

            if (i >= 3 && i <= 10) {

            timeFormatPace(paceMinutes, paceSeconds); System.out.print("\t\t "); timeFormat10K(tenKMinutes, tenKSeconds); System.out.print("\t\t\t ");
            timeFormatMarathon(marathonHours, marathonMinutes, marathonSeconds);
            System.out.println();
            }
     }  
}

Answer 1

我认为这是您想要做的（非常简洁）：

public static void main(String[] args) {
    int pace = 100; // or initialise to whatever

    for(int i = 0; i < 10; i++) {
        // do something

        pace = pace + 30; // or equivalently, pace += 30
    }
}

将来，请尝试将问题减少到minimal, complete and verifiable example。这样做的过程通常可以帮助您自己解决问题，但至少可以使其他人更容易解决问题。

此外，如果您知道程序编写不正确，请修复它！写得好，简洁的模块化程序更容易推论。凌乱，复杂的代码很难。您将以更少的调试时间来感谢自己，并且也会获得更好的成绩。

在for循环中更改全局变量的值

1 个答案: