008 计算某一日是这一年的第几天

#include<stdio.h>
//判断是否为闰年
int isleap(int year){
    int leap;
    leap = year%400==0 || (year%4==0 &&year%100!=0);
    return leap;
}
//计算该日是这一年的第几天，并作为函数值返回
int fun(int year,int month,int day){
    int table[13] = {0,31,28,31,30,31,30,31,31,30,31,30,31};
    int days = 0,i;
    for(i=1;i<month;i++){
        days = days + table[i];
    }
    days += day;
    if(isleap(year) && month>2){
        days += 1;
    }
    return days;
}
void main(){
    int year,month,day,days;
    printf("请输入年、月、日:");
    scanf("%d%d%d",&year,&month,&day);
    days = fun(year,month,day);
    printf("%d年%d月%d日是该年的第%d天\n",year,month,day,days);

}

演示地址：https://tool.lu/coderunner/?id=5bq