《C语言及程序设计》实践参考—

【项目6-日期结构体】

（1）定义一个结构体变量（包括年、月、日），要求输入年、月、日，计算输出该日是该年的第几天。

#include 
     
      struct Date{    int year;    int month;    int day;};int main(){    struct Date date;    printf("input year,month,day:");    scanf("%d %d %d", &date.year, &date.month, &date.day);    int days;    //计算days    printf("%d月%d日是%d年的第%d天.\n", date.month, date.day, date.year, days);    return 0;}

[参考解答]

参考解答1：

#include 
     
      struct Date{    int year;    int month;    int day;};int main(){    struct Date date;    printf("input year,month,day:");    scanf("%d %d %d", &date.year, &date.month, &date.day);    int days;    //计算daysswitch(date.month)    {    case 1: days=date.day;      break;    case 2: days=date.day+31;   break;    case 3: days=date.day+59;   break;    case 4: days=date.day+90;   break;    case 5: days=date.day+120;  break;    case 6: days=date.day+151;  break;    case 7: days=date.day+181;  break;    case 8: days=date.day+212;  break;    case 9: days=date.day+243;  break;    case 10: days=date.day+273; break;    case 11: days=date.day+304; break;    case 12: days=date.day+334; break;    }    if ((date.year %4== 0 && date.year % 100 != 0        ||date.year % 400 == 0) && date.month >=3)        days+=1;    printf("%d月%d日是%d年的第%d天.\n", date.month, date.day, date.year, days);    return 0;}

参考解答2：

#include 
     
      struct Date{    int year;    int month;    int day;};int d[13]= {
    0,31,28,31,30,31,30,31,31,30,31,30,31};int main(){    struct Date date;    printf("input year,month,day:");    scanf("%d %d %d", &date.year, &date.month, &date.day);    //计算days    int days=0,i;    for(i=1; i
      
       =3)        days+=1;        //闰年的2月要加1天    printf("%d月%d日是%d年的第%d天.\n", date.month, date.day, date.year, days);    return 0;}

参考解答3：函数版1——用结构体的分量当形参

#include 
     
      struct Date{    int year;    int month;    int day;};int d[13]= {
    0,31,28,31,30,31,30,31,31,30,31,30,31};int days(int,int,int);int main(){    struct Date date;    printf("input year,month,day:");    scanf("%d %d %d", &date.year, &date.month, &date.day);    //计算days    int d=days(date.year,date.month,date.day);    printf("%d月%d日是%d年的第%d天.\n", date.month, date.day, date.year, d);    return 0;}int days(int yy,int mm,int dd){    int n=0,i;    for(i=1; i
      
       =3)        n+=1;       //闰年的2月要加1天    return n;}

参考解答4：函数版2——用结构体整体作为参数

#include 
     
      struct Date{    int year;    int month;    int day;};int d[13]= {
    0,31,28,31,30,31,30,31,31,30,31,30,31};int days(struct Date);int main(){    struct Date date;    printf("input year,month,day:");    scanf("%d %d %d", &date.year, &date.month, &date.day);    printf("%d月%d日是%d年的第%d天.\n", date.month, date.day, date.year, days(date));    return 0;}int days(struct Date ymd){    int n=0,i;    for(i=1; i
      
       =3)        n+=1;       //闰年的2月要加1天    return n;}

（2）输入两个人的生日，求出他们相差多少天。

[参考解答]

#include 
     
      struct Date{    int year;    int month;    int day;} ;int daysOfMonth[13]= {
    0,31,28,31,30,31,30,31,31,30,31,30,31};int day(struct Date);  //计算出日期d和1900年1月1日差多少天int main(){    struct Date date;    int d1=0,d2=0,t;//d1和d2分别代表两个人的生日和1900年1月1日相差多少天    printf("第一个人的出生日期：");    scanf("%d %d %d", &date.year, &date.month, &date.day);    d1=day(date);    printf("第二个人的出生日期：");    scanf("%d %d %d", &date.year, &date.month, &date.day);    d2=day(date);    //对两个人的生日，求出了和1900年1月1日相差多少天（d1和d2），下面相减    t=d2-d1;    if(t<0)    {        t=-t;//若出现负数，则将其化为正数    }    printf("两人生日相差%d天.\n", t);    return 0;}int day(struct Date d){    int days=0,i;    for(i=1900; i
      
       =3 && ((d.year %4== 0 && d.year % 100 != 0) ||d.year % 400 == 0))        days+=1;        //当年为闰年且进入了3月，还要加1天    return days;  //生日到1900年1月1日共多少天}