20.c

这是一个经过本人一个月的时间自己做的关于c的小程序

#include<stdio.h>

void C_program004()
{
	int year,month,day;
	int count=0,flag=0;
	printf("请输入年月日：\n");
	
	scanf("%d.%d.%d",&year,&month,&day);
	if(year%400==0||(year%4==0&&year%100!=0))
	{
		flag=1;
	}
	if(month==1)
		count=day;
	if(month==2)
		count=31+day;
	if(month>=3)
	{
		if(flag==1)
			count=1;
		else
			count=0;
	}
	switch(month)
	{

	case 3:
		count=count+31+28+day;
		break;
	case 4:
		count=count+31+30+28+day;
		break;

	case 5:
		count=count+31*2+28+day;
		break;
	case 6:
		count=count+31*3+30+28+day;
		break;
	case 7:
		count=count+31*3+30*2+28+day;
		break;
	case 8:
		count=count+31*4+30*2+28+day;
		break;
	case 9:
		count=count+31*5+30*2+28+day;
		break;
	case 10:
		count=count+31*5+30*3+28+day;
		break;
	case 11:
		count=count+31*6+30*3+28+day;
		break;
	case 12:
		count=count+31*6+30*4+28+day;
		break;
	default:
		break;

	}
	printf("该日是这一年的第几日：\n");
	printf("count=%d\n",count);
		
	

	

}