输入一个日期，并计算出该日期为该年里的第几天

#include <stdio.h>
#include <stdbool.h>

int days[13] = {0,31,28,31,30,31,30,31,31,30,31,30,31};
bool is_leap_year(int year)
{
    if((year % 400 == 0) || (year % 4 == 0) && (year % 100 != 0))
        return true;
    else
        return false;
}
int main(int argc, char *argv[])
{
    int i;
    int year, month, day;
    int total = 0;
    printf("Please input a date:");
    scanf("%d%d%d", &year, &month, &day);
    for(i = 1; i < month; i++)
        total += days[i];
    total += day;
    if(is_leap_year(year) && month > 2)
            total ++;
    printf("The %dth day of the year %d.\n",total,year);
    return 0;
}