1 //定义一个结构体变量，给定年月日确定这一天是一年中的第几天，（考虑闰年问题）
2 #include<stdio.h>
3 struct
4 {
5 int year;
6 int month;
7 int day;
8 }date;
9
10 int main()
11 {
12 int days;
13 printf("input year,month,day:\n");
14 scanf("%d,%d,%d", &date.year, &date.month, &date.day);
15 switch (date.month)
16 {
17 case 1:days = date.day; break;
18 case 2:days = date.day + 31; break;
19 case 3:days = date.day + 59; break;
20 case 4:days = date.day + 90; break;
21 case 5:days = date.day + 120; break;
22 case 6:days = date.day + 151; break;
23 case 7:days = date.day + 181; break;
24 case 8:days = date.day + 212; break;
25 case 9:days = date.day + 243; break;
26 case 10:days = date.day + 273; break;
27 case 11:days = date.day + 304; break;
28 case 12:days = date.day + 334; break;
29 }
30 if((date.year % 4 == 0 && date.year % 100 != 0
31 || date.year % 400 == 0) && date.month >=3)
32 days += 1;
33 printf("%d",days);
34 return 0;
35 }
