#include<stdio.h>
int main (void)
{
int year1,year2,month1,month2,date1,date2,i,j,total_year_days=0,total_month_days1=0,total_month_days2=0,total_days;
printf("pealse input your birth day(year,month,date):\n");                                                              
scanf("%d,%d,%d",&year1,&month1,&date1);
printf("pealse input nowaday day(year,month,date):\n");
scanf("%d,%d,%d",&year2,&month2,&date2);
    for(i=year1;i<year2;i++)
    {
    if(i%4==0&&i%100!=0||i%400==0)
    total_year_days=total_year_days+366;
    else
    total_year_days=total_year_days+365;
    }
    for(j=1;j<month1;j++)
    {
    if(j==1,j==3,j==5,j==7,j==8,j==10,j==12)
        total_month_days1=total_month_days1+31;
    if(j==4,j==6,j==9,j==11)
        total_month_days1=total_month_days1+30;
        if(j==2)
        {
            if(year1%4==0&&year1%100!=0||year1%400==0)
            total_month_days1=total_month_days1+29;
            else
            total_month_days1=total_month_days1+28;
        }
    }
    for(j=1;j<month2;j++)
    {
    if(j==1,j==3,j==5,j==7,j==8,j==10,j==12)
        total_month_days2=total_month_days2+31;
    if(j==4,j==6,j==9,j==11)
        total_month_days2=total_month_days2+30;
        if(j==2)
        {
            if(year2%4==0&&year2%100!=0||year2%400==0)
            total_month_days2=total_month_days2+29;
            else
            total_month_days2=total_month_days2+28;
        }
    }
total_days=total_year_days+total_month_days2+date2-total_month_days1-date1;
printf("%d\n",total_days);
return 0;
}
/*year1,month1,date1是出生年月日,year2,month2,date2是今天年月日，total_year_days是从出生年到今年上一年总天数,total_month_days1=0出生年份1月到出生前一月总天数,total_month_days2=0今年1月到这个月前一月总天,total_days活了的天数。
主要问题：比如1990.3.11到1991~2011.1~3.1~30是对的如果现在月份大于出生月份就不对了！
请学长们帮帮忙

意思是不是说这个输出是错误的？？？

对，是错的，应该是7734.从1990.3.11到2011.5.14

#include<stdio.h>
int main (void)
{
    int year1, year2, month1, month2, date1, date2, i,
        j, total_year_days=0, total_month_days1=0,
        total_month_days2=0, total_days;
   
    printf("pealse input your birth day(year,month,date):\n");  
   
    scanf("%d,%d,%d",&year1,&month1,&date1);

    printf("pealse input nowaday day(year,month,date):\n");

    scanf("%d,%d,%d",&year2,&month2,&date2);

    for(i=year1;i<year2;i++)
    {
        if(i%4==0&&i%100!=0||i%400==0)
            total_year_days = total_year_days+366;
        else
            total_year_days = total_year_days+365;
    }
    for(j=1;j<month1;j++)
    {
        if(j==1 || j==3 || j==5 || j==7 || j==8 || j==10 || j==12)
            total_month_days1=total_month_days1+31;
        if(j==4 || j==6 || j==9 || j==11)
            total_month_days1=total_month_days1+30;
        if(j==2)
        {
            if(year1%4==0&&year1%100!=0||year1%400==0)
                total_month_days1=total_month_days1+29;
            else
                total_month_days1=total_month_days1+28;
        }
    }
    for(j=1;j<month2;j++)
    {
        if(j==1 || j==3 || j==5 || j==7 || j==8 || j==10 || j==12)
            total_month_days2=total_month_days2+31;
        if(j==4 || j==6 || j==9 || j==11)
            total_month_days2=total_month_days2+30;
        if(j==2)
        {
            if(year2%4==0&&year2%100!=0||year2%400==0)
                total_month_days2=total_month_days2+29;
            else
                total_month_days2=total_month_days2+28;
        }
    }

    total_days= total_year_days + total_month_days2 + date2 - total_month_days1 - date1;

    printf("%d\n",total_days);

    return 0;
}

if(j==1,j==3,j==5,j==7,j==8,j==10,j==12)
知道逗号表达式 怎么用吗？
依次计算每个表达式的值  但是只取最后一个

啊，谢谢，学长。。太谢谢了。感谢，哈哈，辛苦了