【c++】日期类相关实践：计算日期到天数转换、日期差值

 相关文章：日期类（运算符重载应用）详细版

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目录

前言

实践1：计算日期到天数转换

题目

方法

关键代码

完整代码

实践2：日期差值

题目

方法

关键代码

完整代码 

💗感谢阅读！💗

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前言

在上篇文章中（【c++】类与对象实践：日期类（运算符重载应用）详细版），我们对日期类进行一个完整的实现！

那么接下来我们可以学以致用，完成下列题目！

计算日期到天数转换_牛客题霸_牛客网

日期差值_牛客题霸_牛客网 (nowcoder.com)

实践1：计算日期到天数转换

题目

​​​​​计算日期到天数转换_牛客题霸_牛客网 (nowcoder.com)

方法

获取每月天数  int GetMonthDays(int year, int month) ;

判断闰年：

不能被100整除能被4整除 或 能被400整除。
平年二月28天；
闰年29天。
1 3 5 7 8 10 12 月有31天
4 6 9 11 月有30天

日期类中实现的前置++重载， Date& operator++() ;

日期类中实现的工具方法，日期差值计算  int operator-(const Date& d) const ;

关键代码

int GetMonthDays(int year, int month) {static int monthDays[13] {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};if (month == 2 && ((year % 4 == 0 && year % 100 != 0) || year % 400 == 0))return 29;elsereturn monthDays[month];}Date& operator++() {*this += 1;return *this;}int operator-(const Date& d) const {Date max = *this;Date min = d;int flag = 1;int cnt = 0;if (*this < d) {max = d;min = *this;flag = -1;}while (min != max) {++cnt;++min;}return cnt * flag;}int TheDayOfYear() {return (*this - Date(_year, 1, 1)) + 1;}

完整代码

#include <iostream>
using namespace std;
class Date {public:Date(int year = 0, int month = 0, int day = 0) {_year = year;_month = month;_day = day;}bool operator>(const Date& d) const {if (this->_year > d._year)return true;else if (this->_year == d._year && this->_month > d._month)return true;else if (this->_year == d._year && this->_month == d._month &&this->_day > d._day)return true;elsereturn false;}bool operator==(const Date& d) const {if (this->_year == d._year&& this->_month == d._month&& this->_day == d._day)return true;elsereturn false;}bool operator!=(const Date& d) const {return !(*this == d);}bool operator<(const Date& d) const {return !(*this > d || *this == d);}Date& operator-=(int day) {if (day < 0) {*this += -day;return *this;}_day -= day;while (_day <= 0) {_month--;if (_month == 0) {_month = 12;_year--;}_day += GetMonthDays(_year, _month);}return *this;}Date& operator+=(int day) {if (day < 0) {*this -= -day;return *this;}_day += day;while (_day > GetMonthDays(_year, _month)) {_day -= GetMonthDays(_year, _month);_month++;if (_month == 13) {_month = 1;_year++;}}return *this;}int GetMonthDays(int year, int month) {static int monthDays[13] {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};if (month == 2 && ((year % 4 == 0 && year % 100 != 0) || year % 400 == 0))return 29;elsereturn monthDays[month];}Date& operator++() {*this += 1;return *this;}int operator-(const Date& d) const {Date max = *this;Date min = d;int flag = 1;int cnt = 0;if (*this < d) {max = d;min = *this;flag = -1;}while (min != max) {++cnt;++min;}return cnt * flag;}int TheDayOfYear() {return (*this - Date(_year, 1, 1)) + 1;}private:int _year;int _month;int _day;
};int main() {int year, month, day;while (cin >> year >> month >> day) {Date d(year, month, day);cout << d.TheDayOfYear() << endl;}return 0;
}

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实践2：日期差值

题目

日期差值_牛客题霸_牛客网 (nowcoder.com)

方法

轻而易举，在日期类中，我们已经实现了对于计算日期差值的工具方法。

对于这道题目，我们可以直接套用！！

关键代码

 void getDaynums(const Date& d) {Date max = d;Date min = *this;if (!(max > min)) {max = *this;min = d;}int day = 0;while (min != max) {min++;day++;}day++;cout << day << endl;}

完整代码 

#define _CRT_SECURE_NO_WARNINGS 1
#include <iostream>
using namespace std;class Date {private:int  _year;int _day;int _month = 0;int getMonthDay(int year, int month) {int monthArr[13] = { 0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };//闰年 二月不同if (month == 2 && ((year % 400 == 0) || (year % 4 == 0 && year % 100 != 0))) {return 29;}return monthArr[month];}public:Date(int year, int month, int day) : _year(year), _month(month), _day(day) {  }bool operator>(const Date& d) {if (_year > d._year) {return true;} else if (_year == d._year && _month > d._month) {return true;} else if (_year == d._year && _month == d._month && _day > d._day) {return true;}return false;}bool operator==(const Date& d) {if (_year == d._year && _month == d._month && _day == d._day) {return true;}return false;}Date& operator-=(int day) {if (day < 0) {return *this += (-day);}_day -= day;while (_day < 0) {_month--;if (_month == 0) {_month = 12;_year--;}_day += getMonthDay(_year, _month);}return *this;}bool operator != (const Date& d) {if (*this == d)return false;return true;}Date& operator+=(int day) {// a+=b,a本身变化了，因此最后返回aif (day < 0) {return *this -= day;}_day += day;while (_day > getMonthDay(_year, _month)) { //天数已经超过当前月份_day -= getMonthDay(_year, _month);_month++;if (_month > 12) {_year++;_month = 1;}}return *this;}Date operator++(int) {Date temp(*this);*this += 1;return temp;}void getDaynums(const Date& d) {Date max = d;Date min = *this;if (!(max > min)) {max = *this;min = d;}int day = 0;while (min != max) {min++;day++;}day++;cout << day << endl;}};int main() {int day1, day2, mon1, mon2, year1, year2;scanf("%4d%2d%2d", &year1, &mon1, &day1);scanf("%4d%2d%2d", &year2, &mon2, &day2);Date d(year1, mon1, day1);Date d2(year2, mon2, day2);d.getDaynums(d2);
}
// 64 位输出请用 printf("%lld")

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💗感谢阅读！💗

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