//确保输入的对应月份的日期是正确的
for(;;)
{
//获取日期数据
printf("please input day:");
scanf("%d",&day);
//判断输入的日期是否真的存在,也是防止错误输入时程序计算错误但是并不报错
if((month==2&&leap==1&&day<=29)||(month==2&&leap==0&&day<=28))
break;
else if((month==1||month==3||month==5||month==7||month==8||month==10||month==12)&&day<=31)
break;
else if((month==4||month==6||month==9||month==11)&&day<=30)
break;
else printf("date error\n");
}
switch(month)
{
case 1:sum=0;break;
case 2:sum=31;break;
case 3:sum=59;break;
case 4:sum=90;break;
case 5:sum=120;break;
case 6:sum=151;break;
case 7:sum=181;break;
case 8:sum=212;break;
case 9:sum=243;break;
case 10:sum=273;break;
case 11:sum=304;break;
case 12:sum=334;break;
//default:printf("date error\n");break;