年月日转换－指针法

[starcat]

想用数组指针试试。不想用参考答案里的字符指针方法。
不知道怎么摆平编译时的两个报错消息，请帮帮忙，谢谢。

#include <stdio.h>
static char daytab[][13] = {
{0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31},
{0, 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}
};
static char (*arrptr)[13];
arrptr = daytab;


int day_of_year(int year, int month, int day)
{
int i, leap;
leap = year % 4 == 0 && year %100 != 0 || year % 400 == 0;
for (i = 1; i < month; i++)
day += *(*(arrptr+leap) + i);
return day;
}

void month_day(int year, int yearday, int *pmonth, int *pday)
{
int i, leap;
leap = year % 4 == 0 && year %100 != 0 || year % 400 == 0;
for (i = 1; yearday > *(*(arrptr+leap) + i); i++)
yearday -= *(*(arrptr+leap) + i);
*pmonth = i;
*pday = yearday;
}

int main()
{
int year, month, yearday, day;
int *pmonth, *pday;
printf("Enter the year, month and day:\n");
scanf("%d%d%d", &month, &day, &year);
printf("the %dth day of the year.\n", day_of_year(year, month, day));

printf("Enter the year and yearday:\n");
scanf("%d%d", &year, &yearday);
printf("the %dth day of month %d.\n", *pmonth, *pday);

return 0;
}

[baihacker]

#include <stdio.h> 
static char daytab[][13] = { 
    {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}, 
    {0, 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31} 
}; 
static char (*arrptr)[13] = daytab; //像这样


int day_of_year(int year, int month, int day) 
{ 
    int i, leap; 
    leap = year % 4 == 0 && year %100 != 0 || year % 400 == 0; 
    for (i = 1; i < month; i++) 
  day += *(*(arrptr+leap) + i); 
    return day; 
} 

void month_day(int year, int yearday, int *pmonth, int *pday) 
{ 
    int i, leap; 
    leap = year % 4 == 0 && year %100 != 0 || year % 400 == 0; 
    for (i = 1; yearday > *(*(arrptr+leap) + i); i++) 
yearday -= *(*(arrptr+leap) + i); 
    *pmonth = i; 
    *pday = yearday; 
} 

int main() 
{ 
    int year, month, yearday, day; 
    int *pmonth, *pday; 
    printf("Enter the year, month and day:\n"); 
    scanf("%d%d%d", &month, &day, &year); 
    printf("the %dth day of the year.\n", day_of_year(year, month, day)); 

    printf("Enter the year and yearday:\n"); 
    scanf("%d%d", &year, &yearday); 
    printf("the %dth day of month %d.\n", *pmonth, *pday); 

    return 0; 
} 

[mstlq]

只要搞定编译错误就可以了吗^_^？
那么请把arrptr = daytab这一句语句放入main函数中……

好了，楼主可以开始调试了，good luck^_^

[allen1986]

这个是网上找的解释:

我的观点是这样的：
由于i是全局变量，所以它将静态分配到内存的全局静态区；
所以当你
int i；
i＝10；
编译器会默认是两个不同的全局变量，所以先打印一条“error C4430: 缺少类型说明符 - 假定为 int。注意: C++ 不支持默认 int“，然后编译器因为两个变量的名字相同，接着有第二条”error C2086: “int q”: 重定义”

所以我们一般定义全局变量都是在声明的同时赋初值！

[黄舒颖 咸丫蛋]

printf("Enter the year, month and day:\n");
scanf("%d%d%d", &month, &day, &year);

亲自动手调试了好一会儿，发现卡在这里

[starcat]

[Quote=引用 8 楼 mu_yang 的回复:]
static char daytab[][13] = {
    {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31},
    {0, 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}
};
=========
这个看着就别扭
[/Quote]

这是照搬Dennis Ritchie的写法

[wanghao111]

[Quote=引用 1 楼 baihacker 的回复:]
C/C++ code#include<stdio.h>staticchar daytab[][13]= {
{0,31,28,31,30,31,30,31,31,30,31,30,31},
{0,31,29,31,30,31,30,31,31,30,31,30,31}
};staticchar (*arrptr)[13]= daytab;//像这样int day_of_yea¡­
[/Quote]
hacker

[FigoZhu]

[Quote=引用 4 楼 vshuang 的回复:]
printf("Enter theyear, month and day:\n");
scanf("%d%d%d",&month, &day, &year);

亲自动手调试了好一会儿，发现卡在这里
[/Quote]

scanf("%d-%d-%d",&month, &day, &year);

输入的时候，2009-8-3

[ies_sweet]

[Quote=引用 3 楼 allen1986 的回复:]
这个是网上找的解释:

我的观点是这样的：
由于i是全局变量，所以它将静态分配到内存的全局静态区；
所以当你
int i；
i＝10；
编译器会默认是两个不同的全局变量，所以先打印一条“error C4430: 缺少类型说明符 - 假定为 int。注意: C++ 不支持默认 int“，然后编译器因为两个变量的名字相同，接着有第二条”error C2086: “int q”: 重定义”

所以我们一般定义全局变量都是在声明的同时赋初值！

[/Quote]

更倾向于在运行时赋初值。

[mu_yang]

static char daytab[][13] = {
{0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31},
{0, 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}
};
=========
这个看着就别扭