编写一个函数,以年,月,日为参数,返回该日是星期几.
提示:以一个已知日期为参照,例如1980-01-01为星期二.
(会的朋友请帮帮忙,谢谢.)
我只知道前面的一部分,但不知后面的函数是怎样的.
main()
{
int i,a,b,c;
printf("\nPlease input year,month,day:");
scanf("%d,%d,%d",&a,&b,&c);
i=Get Week(a,b,c);
printf("\n%d-%d-%d is week %d",a,b,c,i );
getch();
}

在scanf("%d,%d,%d",&a,&b,&c);里的那些%后面的d啊,f啊是什么意思啊？我在书上找不到不明白可能我是自学的吧！没人说所以问一下各位路过的！

("%d,%d,%d",&a,&b,&c)中的d为实形 ,,简单的说就是带小 数的数字.建议多看一下C的书 都有介绍的.

int IsLeap(int year)//判断是否为闰年
{
if(year%4==0&&year%100!=0||year%400==0)
return(1);
return(0);
}
void Get_Week(int y,int m,int d)
{
long nday=0;
int i=1980;
while(i<y)//处理年份
{
if(IsLeap(i)==1)
nday+=366;
else
nday+=365;
i++;
}
i=1;
while(i<m)//处理月份
{
switch(i)
{
case 1:
case 3:
case 5:
case 7:
case 8:
case 10:
case 12:dayn+=31;break;
case 4:
case 6:
case 9:
case 11:dayn+=30;break;
case 2:
{
if(IsLeap(y)==1)
nday+=29;
else
nday+=28;
break;
}
}
}
nday+=d;//处理天数
switch(nday%7)//总天数对7求模
{
case 5:printf("Sunday\n");break;
case 6:printf("Monday\n");break;
case 0:printf("Tuesday\n");break;
case 1:printf("Wednesday\n");break;
case 2:printf("Thursday\n");break;
case 3:printf("Friday\n");break;
case 4:printf("Saturday\n");break;
}
}


/*直接在Get_Week输出星期，不知道是否满足楼主的要求，程序尚未调式，请楼主调试一下，大概思想就是这样的，呵呵*/

在Get_Week()函数调用前加个printf("\n%d-%d-%d is",a,b,c);就OK 了

先谢谢5楼的朋友,麻烦你再看一下哪里的修改,运行时1980年1月1日是星期三而不是
星期二,而2006年7月15日却是星期1,正确应该是星期六.
main()
{
int a,b,c;
printf("\nPlease input year,month,day:");
scanf("%d,%d,%d",&a,&b,&c);

printf("%d-%d-%d is ",a,b,c);
Get_Week(a,b,c);
getch();
}

int IsLeap(int year)
{
if(year%4==0&&year%100!=0||year%400==0)
return(1);
return(0);
}
int Get_Week(int y,int m,int d)
{
long nday=0;
int i=1980;
for(i=1980;i<y;i++)
{
if(IsLeap(i)==1)
nday+=366;
else
nday+=365;

}

while(i<m)
{
switch(i)
{
case 1:
case 3:
case 5:
case 7:
case 8:
case 10:
case 12:nday+=31;break;
case 4:
case 6:
case 9:
case 11:nday+=30;break;
case 2:
{
if(IsLeap(y)==1)
nday+=29;
else
nday+=28;
break;
}

}

}

nday+=d;
switch(nday%7)
{
case 5:printf("Sunday\n");break;
case 6:printf("Monday\n");break;
case 0:printf("Tuesday\n");break;
case 1:printf("Wednesday\n");break;
case 2:printf("Thursday\n");break;
case 3:printf("Friday\n");break;
case 4:printf("Saturday\n");break;
}
}

#include<stdio.h>
int IsLeap(int year)//判断是否为闰年
{
if(year%4==0&&year%100!=0||year%400==0)
return(1);
return(0);
}
void Get_Week(int y,int m,int d)
{
long nday=0;
int i=1980;
while(i<y)//处理年份
{
if(IsLeap(i)==1)
nday=nday+366;
else
nday=nday+365;
i++;
}
i=1;
while(i<m)//处理月份
{
switch(i)
{
case 1:
case 3:
case 5:
case 7:
case 8:
case 10:
case 12:nday=nday+31;break;
case 4:
case 6:
case 9:
case 11:nday=nday+30;break;
case 2:
{
if(IsLeap(y)==1)
nday=nday+29;
else
nday=nday+28;
break;
}
}
i++;
}
nday=nday+d-1;//处理天数
nday=nday%7;
switch(nday)//总天数对7求模
{
case 5:printf("Sunday\n");break;
case 6:printf("Monday\n");break;
case 0:printf("Tuesday\n");break;
case 1:printf("Wednesday\n");break;
case 2:printf("Thursday\n");break;
case 3:printf("Friday\n");break;
case 4:printf("Saturday\n");break;
}
}

int main()
{
int a,b,c;
printf("\nPlease input year,month,day:");
scanf("%d%d%d",&a,&b,&c);
printf("\n%d-%d-%d is week ",a,b,c);
Get_Week(a,b,c);
return(0);
}
/*我已经调试过了,可以满足楼主的要求*/

不好意思上次没有调试,所以忽律了一些细节.

那这个程序只能算出1980以后的日子咯?
对吗?