新人和老人对于c语言程序的理解

最新推荐文章于 2025-01-04 13:57:55 发布

原创最新推荐文章于 2025-01-04 13:57:55 发布 · 291 阅读

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CC 4.0 BY-SA版权

本文通过两个示例对比展示了如何使用C语言来判断输入年份中某个月的具体天数，包括考虑闰年的特殊情况。

输入年月，要求输出这个月有多少天！

例如：输入 2017.1

输出 31

新人我写的：

#include <stdio.h>
#include <math.h>

int main ()
{
int year,mouth;
scanf("%d.%d",&year,&mouth);

if (year % 4 == 0)
{
if (year % 100 == 0)
{
switch (mouth)
{
case 1:
case 3:
case 5:
case 7:
case 8:
case 10:
case 12:
printf("31");
break;
case 2:
printf("28");
break;

case 4:
case 6:
case 9:
case 11:
printf("30");
break;
default:
printf("输入错误，请重新输入年月 xxxx.x");
break;
}
}
else
{
switch (mouth)
{
case 1:
case 3:
case 5:
case 7:
case 8:
case 10:
case 12:
printf("31");
break;
case 2:
printf("29");
break;

case 4:
case 6:
case 9:
case 11:
printf("30");
break;
default:
printf("输入错误，请重新输入年月 xxxx.x。");
break;
}
}

if (year % 400 == 0)
{
switch (mouth)
{
case 1:
case 3:
case 5:
case 7:
case 8:
case 10:
case 12:
printf("31");
break;
case 2:
printf("29");
break;

case 4:
case 6:
case 9:
case 11:
printf("30");
break;
default:
printf("输入错误，请重新输入年月 xxxx.x。");
break;
}
}
else
{
switch (mouth)
{
case 1:
case 3:
case 5:
case 7:
case 8:
case 10:
case 12:
printf("31");
break;
case 2:
printf("28");
break;

case 4:
case 6:
case 9:
case 11:
printf("30");
break;
default:
printf("输入错误，请重新输入年月 xxxx.x。");
break;
}
}

}
else
{
switch (mouth)
{
case 1:
case 3:
case 5:
case 7:
case 8:
case 10:
case 12:
printf("31");
break;
case 2:
printf("28");
break;

case 4:
case 6:
case 9:
case 11:
printf("30");
break;
default:
printf("输入错误，请重新输入年月 xxxx.x。");
break;
}
}

return 0;

}

老手写的：

#include <stdio.h>

int main ()
{
int year,mouth;
scanf("%d.%d",&year,&mouth);

switch (mouth)
{
case 1:
case 3:
case 5:
case 7:
case 8:
case 10:
case 12:
printf("31");
break;
case 2:
if ( year %4 == 0 && year % 100 != 0 || year % 400 ==0)
{
printf("29");
}
else
{
printf("28");
}
break;

case 4:
case 6:
case 9:
case 11:
printf("30");
break;
default:
printf("输入错误，请重新输入年月 xxxx.x");
break;
}

return 0;

由此可见我还是需要努力学习的！！！