15、輸入年月日，判斷這一天是該年的第幾天。

/*
輸入年月日，判斷這一天是該年的第幾天。
 */

#include <stdio.h>
#include <stdlib.h>

typedef struct Data
{
    int year;
    int month;
    int day;
}Data;

int calculate(Data data)
{
    int num = 0;
    switch(data.month - 1)
    {
        case 11: num += 30;
        case 10: num += 31;
        case 9: num += 30;
        case 8: num += 31;
        case 7: num += 31;
        case 6: num += 30;
        case 5: num += 31;
        case 4: num += 30;
        case 3: num += 31;
        case 2: num += 28;
        case 1: num += 31;
    }
    return num;
}

int getDays4(Data data)
{
    int num = 0;
    if(data.month == 1)
        return num + data.day;
    num = calculate(data);
    if((data.year % 4 == 0 && data.year % 100 != 0) || data.year % 400 == 0)
        return num + 1 + data.day;
    else
        return num + data.day;
}

int main()
{
    int num = 0;
    Data data = {0,0,0};
    scanf("%d", &data.year );
    scanf("%d", &data.month );
    scanf("%d", &data.day );
    int days = getDays4(data);
    printf("%d",days);
    return 0;
}