Seventh week the second item-friend class

/*copyright (c) 2016, College of Computer and Control engineering, Yantai University 02.*all rights reserved.03.* file name: main.cpp04.* Author: Tian Zhiwei 05.* finish Date: May 9, 2016 06.* version Number: v1.007.*08.* problem Description: Friend Time class 09. Input Description: 10.* Output Description: Month Day hour minute seconds */#include <iostream>using namespace Std;class Date;    Advance reference to the Date class declares class Time{public:time (Int,int,int);  void Add_a_second (Date &);  Add 1 seconds, 1 seconds after the next day, to the next month, the next year, void Display (Date &);    Display time, Format: Month/day/year: minutes: seconds Private:int hour;    int minute; int sec;};    Class Date{public:date (Int,int,int); Friend class time;    Time is the friend class of date Private:int month;    int day; int year;};    Time::time (int a,int b,int c) {hour=a;    Minute=b; Sec=c;}    Date::D ate (int x,int y,int z) {month=x;    Day=y; Year=z;}; void Time::add_a_second (DATE&AMP;D1) {sec=sec+1;}        void time::d isplay (DATE&AMP;D1) {if (sec>=60) {minute=sec/60+minute;    sec=sec%60;        } if (minute>=60) {hour=minute/60+hour;    minute=minute%60; } if (hour>=24) {D1.DAY=D1.DAY+HOUR/24;    hour=hour%24;        } if (d1.day>31) {d1.month=d1.day/30+d1.month;    d1.day=d1.day%30;        } if (d1.month>12) {d1.year=d1.month/12+d1.year;    d1.month=d1.month%12; } cout<<d1.month<< "/" <<d1.day<< "/" <<d1.year<< "" <
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Seventh week the second item-friend class