C++ Class Definition model a time data type

#include <iostream>
using namespace std;
class time/*from  w  ww  .j  ava  2 s . c  o  m*/
{
   private:
   int hrs, mins, secs;
   public:
   time() : hrs(0), mins(0), secs(0) //no-arg constructor
   {  }
   //3-arg constructor
   time(int h, int m, int s) : hrs(h), mins(m), secs(s)
   {  }
   void display() const              //format 11:59:59
   { cout << hrs << ":" << mins << ":" << secs; }
   void add_time(time t1, time t2)   //add two times
   {
      secs = t1.secs + t2.secs;      //add seconds
      if( secs > 59 )                //if overflow,
         { secs -= 60; mins++; }     //   carry a minute
      mins += t1.mins + t2.mins;     //add minutes
      if( mins > 59 )                //if overflow,
         { mins -= 60; hrs++; }      //   carry an hour
      hrs += t1.hrs + t2.hrs;        //add hours
   }
};
int main()
{
   const time time1(5, 59, 59);         //creates and initialze
   const time time2(4, 30, 30);         //   two times
   time time3;                          //create another time
   time3.add_time(time1, time2);        //add two times
   cout << "time3 = "; time3.display(); //display result
   cout << endl;
   return 0;
}