六条咸鱼-Wolves-Day10

输入年月日，输出是这年的第多少天.

#include "stdio.h"
void main()
{
  	int year,month,day,sum;
  	printf("请输入年月日：");
  	scanf("%d%d%d",&year,&month,&day);
  		switch(month)
  		{
	  		case  1:sum=day;break;
	  		case  2:sum=31+day;break;
	  		case  3:sum=31+28+day;break;
	  		case  4:sum=31+28+31+day;break;	
	  		case  5:sum=31+28+31+30+day;break;	
	  		case  6:sum=31+28+31+30+31+day;break;	
	  		case  7:sum=31+28+31+30+31+30+day;break;	
	  		case  8:sum=31+28+31+30+31+30+31+day;break;	
	  		case  9:sum=31+28+31+30+31+30+31+31+day;break;	
	  		case 10:sum=31+28+31+30+31+30+31+31+30+day;break;	
	  		case 11:sum=31+28+31+30+31+30+31+31+30+31+day;break;	
	  		case 12:sum=31+28+31+30+31+30+31+31+30+31+30+day;break;	
	  		default:printf("输入错误n");	
  		}
  	if((year%4==0&&year%100!=0||year%400==0)&&month>=2)
  		sum++;
 	printf("这是这一年的第%d天n",sum);
}

输出九九乘法表

#include "stdio.h"
void main()
{
	int i,j,k;
	for(i=1;i<10;i++)
	{
		for(j=1;j<=i;j++)
		{
			k=i*j;
			printf("%d*%d=%-3d",i,j,k);
		}
			printf("n");
	}
	
}