+// A class to encapsulate hr:min representation of time.
+
+class ClockTime {
+public:
+ ClockTime();
+ ClockTime(int hr, int min);
+ ~ClockTime();
+ inline void set_hr(int hr) { _hr = hr; }
+ inline int hr() const { return(_hr); }
+ inline void set_min(int min) { _min = min; }
+ inline int min() const { return(_min); }
+
+ ClockTime operator+ (const ClockTime& t) {
+ int cumMin = _hr * 60 + _min + t.hr() * 60 + t.min();
+ ClockTime t2(cumMin / 60, cumMin % 60);
+ return(t2);
+ }
+ // Operator - has a max difference of 23:59,
+ // and assumes the day has wrapped if the second operand
+ // is larger that the first.
+ // eg. 2:59 - 3:00 = 23:59
+ ClockTime operator- (const ClockTime& t) {
+ int diff = (_hr * 60 + _min) - (t.hr() * 60 + t.min());
+ if(diff < 0) { diff += 24 * 60; }
+ ClockTime t2(diff / 60, diff % 60);
+ return(t2);
+ }
+ friend ostream& operator<< (ostream& out, const ClockTime& t);
+
+private:
+ int _hr;
+ int _min;
+};
+