C、打印用户选择的月份

Question

我正在做一个学校项目，我需要要求像日历一样打印一年和一个月。问题是，当我调试时，它显示全年，而不仅仅是所选的月份。我必须做哪些改变？希望你能帮我!这是我的代码:

int SetFirstDay(int year)
{
    int d;
    int d1, d2, d3;

    d1 = (year - 1.) / 4.0;
    d2 = (year - 1.) / 100.;
    d3 = (year - 1.) / 400.;
    d = (year + d1 - d2 + d3) % 7;
    return d;
}

int main()
{
    int day, month, year, ndays, DayWeek = 0, FirstDay;
    do
    {
        printf("\nEnter the desired year [2000 - 2099]\n");
        scanf_s(" %d", &year);
    } while (year < 2000 || year > 2100);

    do
    {
        printf("\nEnter the desired month [1 - 12]\n");
        scanf_s(" %d", &month);
    } while (month < 1 || month > 12);


    char *months[] = { "January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December" };
    int DayMonth[] = { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
    if ((year % 4 == 0 && year % 100 != 0) || (year % 400 == 0))
        DayMonth[1] = 29;

    FirstDay = SetFirstDay(year);

    for (month = 0; month < 12; month++)   
    {
        ndays = DayMonth[month];
        printf("\n\n--------------%s-----------------\n", months[month]);
        printf("\n  Sun  Mon  Tue  Wed  Thu  Fri  Sat\n");

        for (DayWeek = 0; DayWeek < FirstDay; DayWeek++)
        {
            printf("     ");
        }

        for (day = 1; day <= ndays; day++)
        {
            printf("%5d", day);

            if (++DayWeek > 6)
            {
                printf("\n");
                DayWeek = 0;
            }
            FirstDay = DayWeek;
        }
    }
    printf("\n\n\n");
    system("pause");
    return 0;
}

Answer 1

将用户输入的月份值保存到附加变量中:

int monthTmp = month;

然后在所有 printf 调用前面加上以下带有“月”for 循环的语句:

for (month = 0; month < 12; month++)   
{
    // ...
    if (monthTmp==month) printf(.........

这不是一个优化的解决方案，但非常简单。