Question

求下面C语言程序的算法和设计思想，最好附有程序框图或NS图。

#include<stdio.h>

bool isday(int day,int mouth,int year)
{
int a[12]={31,28,31,30,31,30,31,31,30,31,30,31};
if((year%400==0)||(year%4==0&&year%100!=0)) a[1]++;
if(day>a[mouth-1]||day<1)
return true;
else
return false;
}

void main()
{
int i,year,mouth,day;
int sum,sign;
int a[12]={31,28,31,30,31,30,31,31,30,31,30,31};
do
{
sum=0;sign=0;
puts("请输入年、月、日:");
scanf("%d%d%d",&year,&mouth,&day);
if(((year%400==0)||(year%4==0&&year%100!=0))&&mouth>2)
{
sum=day+1;//闰年，记得加1
}
else sum=day;
for(i=0;i<mouth-1;i++)
sum+=a[i];
if(year<1||mouth<1||mouth>12||isday(day,mouth,year))
{
puts("输入错误，请重新输入：");
sign=1;
}
}while(sign);
printf("为第%d天\n",sum);
}

Answer 1

bool isday(int day,int mouth,int year)//布尔型
{
int a[12]={31,28,31,30,31,30,31,31,30,31,30,31};//基激建立数组，一年每个月的日烂银子数（平年）
if((year%400==0)||(year%4==0&&year%100!=0)) a[1]++;//如果为闰年，2月份加一天
if(day>a[mouth-1]||day<1)//判断天数是否合法
return true;
else
return false;
}

void main()//根据年月日返回该天在一年的哪一天
{
int i,year,mouth,day;
int sum,sign;
int a[12]={31,28,31,30,31,30,31,31,30,31,30,31};
do
{
sum=0;sign=0;
puts("请输入年、月、日:");
scanf("%d%d%d",&year,&mouth,&day);
if(((year%400==0)||(year%4==0&&year%100!=0))&&mouth>2)
{
sum=day+1;//闰年，记得加1
}
else sum=day;
for(i=0;i<mouth-1;i++)
sum+=a[i];//统计天数
if(year<1||mouth<1||mouth>12||isday(day,mouth,year))/搏历袜/判断日期是否合法
{
puts("输入错误，请重新输入：");
sign=1;
}
}while(sign);
printf("为第%d天\n",sum);
}