7-19 计算天数

本题要求编写程序计算某年某月某日是该年中的第几天。

输入格式:
输入在一行中按照格式“yyyy/mm/dd”（即“年/月/日”）给出日期。注意：闰年的判别条件是该年年份能被4整除但不能被100整除、或者能被400整除。闰年的2月有29天。

输出格式:
在一行输出日期是该年中的第几天。

输入样例1:
2009/03/02

输出样例1:
61

输入样例2:
2000/03/02

输出样例2:
62

#include<stdio.h>
int main(){
    int year,mouth,day;
    scanf("%d/%d/%d",&year,&mouth,&day); 
    //printf("%d %d %d",year,mouth,day);
    if(year%4==0){
        if(year%400==0){
            year=1;
            //printf("year为闰年\n"); 
        }else if(year%100!=0){
            year=1;
            //printf("year为闰年\n");
            }            
    }else {
        year=0;
        //printf("year为平年"); 
    }
    if(year==1){
        if(mouth>=3){
            switch(mouth-1){
                case 2:mouth=60;break;
                case 3:mouth=91;break;
                case 4:mouth=121;break;
                case 5:mouth=152;break;
                case 6:mouth=182;break;
                case 7:mouth=213;break;
                case 8:mouth=244;break;
                case 9:mouth=274;break;
                case 10:mouth=305;break;
                case 11:mouth=335;break;
            }
            printf("%d",mouth+day);
        }else{
            switch(mouth-1){
                case 0:mouth=0;break;
                case 1:mouth=31;break;
            }
            printf("%d",mouth+day);
        }

    }else{
        if(mouth>=3){
            switch(mouth-1){
                case 2:mouth=59;break;
                case 3:mouth=90;break;
                case 4:mouth=120;break;
                case 5:mouth=151;break;
                case 6:mouth=181;break;
                case 7:mouth=212;break;
                case 8:mouth=243;break;
                case 9:mouth=273;break;
                case 10:mouth=304;break;
                case 11:mouth=334;break;
            }
            printf("%d",mouth+day);
        }else{
            switch(mouth-1){
                case 0:mouth=0;break;
                case 1:mouth=31;break;
            }
            printf("%d",mouth+day);
        }

    }

    return 0;
}