题目链接

解析

使用数组保存闰年每个月的天数方便计算，之后再判断是否为平年，如果是且月份大于2，就要减去一天

代码

class Solution {
public:
    int dayOfYear(string date) {
        int dayTable[] = {31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
        int year = stoi(date.substr(0, 4));
        int month = stoi(date.substr(5, 2));
        int day = stoi(date.substr(8, 2));
        int dayNum = day;
        for (int i = 1; i < month; i++) {
            dayNum += dayTable[i - 1];
        }
        if (month > 2) {
            if (year % 4 != 0 || ((year % 100 == 0) && (year % 400 != 0))) {
                dayNum--;
            }
        }
        return dayNum;
    }
};