Question

如何获得本月的第一天和最后一天的日期

Answer 1

年和月知道了，第一天显然就是1号了，最后一天根据闫年和月份判断：
#define isleap(y) ((y)%4 == 0 && (y)%100 != 0 || (y)%400 == 0)

int year,month;
scanf("%d,%d", &year, &month);

switch(month)
{
case 1:
case 3:
case 5:
case 7:
case 8:
case 10:
case 12:
printf("31");
break;
case 2:
if (isleap(year))
printf("29");
else
printf("28");
break;
case 4:
case 6:
case 9:
case 11:
printf("30");
break;
default:
printf("error");

}