Writing a clock...

Alright, so, after messing around with Dev-C++, I've managed to come up with a simple clock:

Code:

---

#include <iostream>
#include <windows.h>

using namespace std;

int main()
{
    unsigned short int hours = 0;
    unsigned short int minutes = 0;
    unsigned short int seconds = 0;
    unsigned short int exit = 0;
    string input;
   
    cout<<"Display seconds?\nY/N: ";
    cin>>input;
    cin.ignore();
   
    cout<<"\n\nPlease set the time (hours)\nTime: ";
    cin>>hours;
    cin.ignore();
   
    cout<<"\n\nPlease set the time (minutes)\nTime: ";
    cin>>minutes;
    cin.ignore();
   
    while (exit == 0)
    {
          system("cls");
         
          if (input == "y")
          {
                      if (minutes < 10)
                      {
                                if (seconds < 10)
                                {
                                            cout<<"\n\nCurrent time: "<<hours<<":0"<<minutes<<":0"<<seconds;
                                }
                               
                                else
                                {
                                            cout<<"\n\nCurrent time: "<<hours<<":0"<<minutes<<":"<<seconds;
                                }
                      }
                     
                      else
                      {
                                if (seconds < 10)
                                {
                                            cout<<"\n\nCurrent time: "<<hours<<":"<<minutes<<":0"<<seconds;
                                }
                               
                                else
                                {
                                            cout<<"\n\nCurrent time: "<<hours<<":"<<minutes<<":"<<seconds;
                                }
                      }
                      if (seconds >= 60)
                      {
                                minutes++;
                                seconds = 0;
                      }
                     
                      if (minutes >= 60)
                      {
                                hours++;
                                minutes = 0;
                                seconds = 0;
                      }
                      if (hours >= 13)
                      {
                                hours = 1;
                                minutes = 0;
                                seconds = 0;
                      }
                     
                      seconds++;
                      Sleep (1000);
                     
          }
         
                    if (input == "n")
          {
                   
                      if (minutes < 10)
                      {
                                  cout<<"\n\nCurrent time: "<<hours<<":0"<<minutes;
                      }
                     
                      else
                      {

                                  cout<<"\n\nCurrent time: "<<hours<<":"<<minutes;
                      }
                     
                      if (seconds >= 60)
                      {
                                minutes++;
                                seconds = 0;
                      }
                     
                      if (minutes >= 60)
                      {
                                hours++;
                                minutes = 0;
                                seconds = 0;
                      }
                      if (hours >= 13)
                      {
                                hours = 1;
                                minutes = 0;
                                seconds = 0;
                      }
                     
                      seconds++;
                      Sleep (1000);
          }
    }
    return 0;
}

---

So, it works all fine and dandy, but I'd like to know what could be improved.
(also, is it possible to preformat integers to show 01 instead of 1?)

And yes, I'm definitely not very far along, but writing simple applications amuses me :P

What I'm asking is what would somebody more experienced do differently to achieve the same purpose?

What about delay in processing? It will take extra milliseconds to process the clock maybe longer if you have other stuff going on. It would add up to be a really inaccurate clock I imagine. I couldn't tell you how to deal with this but it is what it is.

Quote:

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I couldn't tell you how to deal with this but it is what it is.

---

One possible way:
GetTickCount at the beginning of the program...
+1000 on each iteration - to calculate next wake up time
GetTickCount before Sleep to calculate current Time
Make Sleep with difference between the currentTime and Next WakeUp time instead of 1000

You need to include the header file <string> to use C++ strings.

Also, the variable exit might be better off as a bool. Not that your program ever exits. :)

Also, couldn't you put that if(input=="y") only around the code that actually deals with seconds instead of duplicating lots of code?

If I was writing a clock program like that, I'd use the time() or clock() function from <ctime> -- but perhaps that just takes the fun out of it. :)

Quote:

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Originally Posted by dwks

Also, the variable exit might be better off as a bool. Not that your program ever exits. :)

---

It would also be better off not being called "exit." That's the name of a standard library function. By declaring a variable called exit you can never call exit() from inside main(). Instead call it "do_exit" or somesuch.

EDIT: Well, I suppose you could call it as ::exit() instead, but it's still confusing.