有意思，看下面程式：

#include <iostream>
using namespace std;

bool isSpecialTime(int hour, int minute)
{
	/*
	[8:20 <= x:yz < 10:40)
	<==> 8.20 <= x.yz < 10.40
	<==> 820 <= 100x + 10y + z  < 1040
	<==> 820 <= 100 * hour + minute  < 1040
	*/

  int result = 100 * hour + minute;
  if(result >= 820 && result < 1040)
	  return true;

  return false;

}

int main()
{
	int hour;
	int minute;
	for(hour = 7; hour < 12; hour++)
	{
		for(minute = 0; minute < 60; minute++)
		{
			if(isSpecialTime(hour, minute))
			{
				if(minute >= 10)
					cout << hour << ":" << minute << endl;
				else
					cout << hour << ":" << "0" << minute << endl;
			}
		}
	}

	return 0;
}