algorithms

时隔一月重新开始leetcode周赛，被教做人....做题进度0/4，有点扎心
number-of-days-between-two-dates

description

搞了半天，没搞明白，看别人题解吧~

请你编写一个程序来计算两个日期之间隔了多少天。
日期以字符串形式给出，格式为 YYYY-MM-DD，如示例所示。
示例 1：
输入：date1 = "2019-06-29", date2 = "2019-06-30"
输出：1
示例 2：
输入：date1 = "2020-01-15", date2 = "2019-12-31"
输出：15

来源：力扣（LeetCode）
链接：https://leetcode-cn.com/problems/number-of-days-between-two-dates
著作权归领扣网络所有。商业转载请联系官方授权，非商业转载请注明出处。

my solution

解决思路，计算两个日期分别距离1970-01-01多少天，再计算差值

class Solution {
public:
    vector<int> months = {-1,31,28,31,30,31,30,31,31,30,31,30,31};
    int daysBetweenDates (string date1, string date2) {
        return abs(getdays(date1)-getdays(date2));
    }
    int isleap(int year){
        return year%4==0 && year%100!=0 || year%400==0;
    }
    
    int getdays(string date) {
        int year = 0, month = 0, day = 0;
        for (int i=0; i<4; ++i) {
            year = year*10 + date[i]-'0';
        }
        for (int i=5; i<7; ++i) {
            month = month*10 + date[i]-'0';
        }
        for (int i=8;i<date.size(); ++i) {
            day = day*10 + date[i]-'0';
        }
        int result = 0;        
        for (int i=1970; i<year; ++i) {
            result += isleap(i)? 366:365;
        }
        for (int i=1; i<month; ++i) {
            result += months[i];
            if (i==2 && isleap(year)) {
                result++;
            }
        }
        result += day;
        return result;
    }
};

complexity

Review

How To Ask Questions The Smart Way
original link

Tips

开始学Java

C++ Vectors are sequence containers representing arrays that can change in size.
Java The Vector class implements a growable array of objects. Like an array, it contains components that can be accessed using an integer index. However, the size of a Vector can grow or shrink as needed to accommodate adding and removing items after the Vector has been created.

我看着这俩没啥区别哈？