为什么答案输出不对啊
键盘上按照年月日的格式输入年份、月和日期,运行程序以后,判断这一天是这一年的第几天。输入描述
标准输入,输入三个整数,即年、月、日(都是正数),以空格间隔,不保证输入的年份和日期是正确的。
输出描述
标准输出,输出这一天是这一年的第几天,如果日期不合法,输出“data error!”。#include<stdio.h>
int main()
{
int year,mon,day,days=0;
scanf("%d%d%d",&year,&mon,&day);
if(year>9999||year<1000) printf("date error!");
else
{if(((year%400==0)||(year%34==0&&year%100!=0))&&mon>2)
days++;
switch(mon)
{
case 1:
{
if(day>31) printf("data error!");
else
{days=day;printf("%d",days);}
break;
}
case 2:
{
if(((year%400==0||(year%4==0||year%100!=0))&&mon>29)||((year%400!=0||(year%4!=0||year%100==0))&&mon>28))printf("data error!");
else
{days=day+31;printf("%d",days);}
break;
}
case 3:
{
if(day>31) printf("data error!");
else
{days=day+59;printf("%d",days);}
break;
}
case 4:
{
if(day>30) printf("data error!");
else
{days=day+90;printf("%d",days);}
break;
}
case 5:
{
if(day>31) printf("data error!");
else
{days=day+120;printf("%d",days);}
break;
}
case 6:
{
if(day>30) printf("data error!");
else
{days=day+151;printf("%d",days);}
break;
}
case 7:
{
if(day>31) printf("data error!");
else
{days=day+181;printf("%d",days);}
break;
}
case 8:
{
if(day>31) printf("data error!");
else
{days=day+212;printf("%d",days);}
break;
}
case 9:
{
if(day>30) printf("data error!");
else
{days=day+243;printf("%d",days);}
break;
}
case 10:
{
if(day>31) printf("data error!");
else
{days=day+273;printf("%d",days);}
break;
}
case 11:
{
if(day>30) printf("data error!");
else
{days=day+304;printf("%d",days);}
break;
}
case 12:
{
if(day>31) printf("data error!");
else
{days=day+334;printf("%d",days);}
break;
}
default:printf("date error!");
}
}
} 问题出在判断闰年的条件上。根据题目要求,闰年的判断条件应该是:年份能被400整除,或者年份能被4整除但不能被100整除。但是在代码中,判断闰年的条件写成了((year%400==0)||(year%34==0&&year%100!=0)) ,这是错误的。
另外,代码中还有一处错误,判断2月份的天数时,使用了错误的逻辑运算符,应该使用||而不是&& 。
修正后的代码如下:
#include <stdio.h>
int main()
{
int year, mon, day, days = 0;
scanf("%d%d%d", &year, &mon, &day);
if (year > 9999 || year < 1000)
printf("data error!");
else
{
if (((year % 400 == 0) || (year % 4 == 0 && year % 100 != 0)) && mon > 2)
days++;
switch (mon)
{
case 1:
if (day > 31)
printf("data error!");
else
{
days = day;
printf("%d", days);
}
break;
case 2:
if (((year % 400 == 0 || year % 4 == 0 && year % 100 != 0) && day > 29) ||
((year % 400 != 0 || year % 4 != 0 && year % 100 == 0) && day > 28))
printf("data error!");
else
{
days = day + 31;
printf("%d", days);
}
break;
case 3:
if (day > 31)
printf("data error!");
else
{
days = day + 59;
printf("%d", days);
}
break;
case 4:
if (day > 30)
printf("data error!");
else
{
days = day + 90;
printf("%d", days);
}
break;
case 5:
if (day > 31)
printf("data error!");
else
{
days = day + 120;
printf("%d", days);
}
break;
case 6:
if (day > 30)
printf("data error!");
else
{
days = day + 151;
printf("%d", days);
}
break;
case 7:
if (day > 31)
printf("data error!");
else
{
days = day + 181;
printf("%d", days);
}
break;
case 8:
if (day > 31)
printf("data error!");
else
{
days = day + 212;
printf("%d", days);
}
break;
case 9:
if (day > 30)
printf("data error!");
else
{
days = day + 243;
printf("%d", days);
}
break;
case 10:
if (day > 31)
printf("data error!");
else
{
days = day + 273;
printf("%d", days);
}
break;
case 11:
if (day > 30)
printf("data error!");
else
{
days = day + 304;
printf("%d", days);
}
break;
case 12:
if (day > 31)
printf("data error!");
else
{
days = day + 334;
printf("%d", days);
}
break;
default:
printf("data error!");
}
}
return 0;
}
这样修正后的代码可以正确判断日期是否合法,并输出这一天是这一年的第几天。 这段代码有以下问题:
1. 第7行的输出应该是"data error!"而不是"date error!"
2. 第11行的年份除以34应该是除以4
3. 在每个case中都需要加上break语句,否则会继续执行下一个case
4. 在第24行到27行的公式中,应该是闰年的情况下mon>2,而不是mon>29或mon>28
5. 最后的default语句不需要输出任何内容
修改后的代码如下:
++
#include <stdio.h>
int main() {
int year, mon, day, days = 0;
scanf("%d%d%d", &year, &mon, &day);
if (year > 9999 || year < 1000)
printf("data error!");
else {
if (((year % 400 == 0) || (year % 4 == 0 && year % 100 != 0)) && mon > 2)
days++;
switch (mon) {
case 1: {
if (day > 31)
printf("data error!");
else {
days = day;
printf("%d", days);
}
break;
}
case 2: {
if ((year % 400 == 0 || (year % 4 == 0 && year % 100 != 0)) && day > 29 ||
(year % 400 != 0 || (year % 4 != 0 || year % 100 == 0)) && day > 28)
printf("data error!");
else {
days = day + 31;
printf("%d", days);
}
break;
}
case 3: {
if (day > 31)
printf("data error!");
else {
days = day + 59;
printf("%d", days);
}
break;
}
case 4: {
if (day > 30)
printf("data error!");
else {
days = day + 90;
printf("%d", days);
}
break;
}
case 5: {
if (day > 31)
printf("data error!");
else {
days = day + 120;
printf("%d", days);
}
break;
}
case 6: {
if (day > 30)
printf("data error!");
else {
days = day + 151;
printf("%d", days);
}
break;
}
case 7: {
if (day > 31)
printf("data error!");
else {
days = day + 181;
printf("%d", days);
}
break;
}
case 8: {
if (day > 31)
printf("data error!");
else {
days = day + 212;
printf("%d", days);
}
break;
}
case 9: {
if (day > 30)
printf("data error!");
else {
days = day + 243;
printf("%d", days);
}
break;
}
case 10: {
if (day > 31)
printf("data error!");
else {
days = day + 273;
printf("%d", days);
}
break;
}
case 11: {
if (day > 30)
printf("data error!");
else {
days = day + 304;
printf("%d", days);
}
break;
}
case 12: {
if (day > 31)
printf("data error!");
else {
days = day + 334;
printf("%d", days);
}
break;
}
default:
printf("data error!");
break;
}
}
return 0;
}
球一个最佳答案谢谢啦!这对我非常重要!{:10_254:}{:10_254:}{:10_254:}
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