A noob in need of help!

HI! Im trying to make a C++ console app. where you give the computer a number and it tries to guess it by process of elimination.
You put in a number for it to guess,
then it sees if it is bigger or smaller than 5000 and goes from there....

Code:

---

while (Guess != SecretNumber)
        {
                Sleep(32);  //slow it down

                if(Guess > SecretNumber)
                {
                        cout << "Ok, so it's bigger than "<< Guess <<"\n\n";
                        Guess = Guess /2;
                        cout << "Um... Is it... " <<Guess<<"??\n";
                }
                else if(Guess < SecretNumber)
                {
                        cout << "Ok, so it's smaller than "<<Guess<<"\n\n";
                        Guess = Guess - (Guess/2);
                        cout << "Um... Is it... " <<Guess<<"??\n";
                }
                else if (SecretNumber == Guess)
                {
                        cout << "yay\n";
                }

---

Could please tell me where I am going wrong and maybe what I need to do [/plea]
;D
Thanks :p

I'm tempted to say this is a generally bad algorithm, but here goes...

Code:

---

Guess = Guess - (Guess/2);

---

should be something like:

Code:

---

Guess+=(Guess/2);
//or
Guess = Guess + (Guess/2);

---

you can also run into this problem... Guess comes to 3, and their number is two.

Code:

---

guess>number
  guess/2
guess<number
  guess+=guess/2

---

this is how it looks to a computer (kinda)

Code:

---

3>2
  3/2=1
1<2
  1/2=0; 0+1=1;

---

then it goes into an infinite loop...
perhaps you should go with the more conventional version of this program: the program picks a random number and the user guesses it.

Or

Code:

---

Guess *= 1.5

---

and

Code:

---

Guess *= 0.5

---

Binary search anyone?

Code:

---

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

using namespace std;

int main()
{
  int number;
  int l, h, m;

  cout<<"Enter a number between 0 and 5000: ";
  if ( !( cin>> number || number < 0 || number > 5000 ) ) {
    cerr<<"I said a number between 0 and 5000...";
    return EXIT_FAILURE;
  }
  l = 0;
  h = 5000;
  cout<<"Hmm";
  while ( true ) {
    m = ( l + h ) / 2;
    cout<<'.';
    if ( number < m )
      h = m - 1;
    else if ( number > m )
      l = m + 1;
    else
      break;
    Sleep ( 500 );
  }
  cout<<"It's "<< m <<", I knew it!"<<endl;
}

---

Prelude! How could you!?!?!!

#include <stdlib.h>

#include <cstdlib>

Sheesh. I expected more from you.

Cool thanx!
I'll get to work!
If I have any more troubles, now I know where to go! :D

P.S. The programme I made prior to this one was one where the computer makes a random number and the user guesses it. [it actually worked!]

P.P.S. Think I might have a crack at making pong after this... these forums are full of pong programmes!!

> Prelude! How could you!?!?!!

I bet she was using Dev-C++, which automatically inserts <stdlib.h> instead of <cstdlib>.

i completely forgot that Dev adds that stuff in... whenever I start a new project, I always erase everything it throws in there... prewritten code just kinda annoys me...

>Sheesh. I expected more from you.
Hmm? What do you mean? (I actually know what you mean, but I want to hear your reasoning before I give you mine ;))

>I bet she was using Dev-C++, which automatically inserts <stdlib.h> instead of <cstdlib>.
Nope, I wrote that in MSVC++ 6. And the choice of header was quite deliberate. ;)

My reasoning is that since it is a C++ program, it should use C++ headers. Since there is a C++ conversion of <stdlib.h> (<cstdlib>), you should use it. I figured that you would at least conform to the standards.

Now let's hear your reasoning.

>Since there is a C++ conversion of <stdlib.h> (<cstdlib> ), you should use it.
The C++ headers wrap everything in the std namespace. This makes things like printf calls look funny. Also, my version of MSVC++ doesn't do this, so if I forget the std:: prefix, I'll be programming outside of the standard unless I use a using directive on std, which I prefer not to do unless I'm exceptionally lazy.

>I figured that you would at least conform to the standards.
The C++ standard gives us the c* headers, but it also requires conformance with standard C. This means that the C .h headers must be supported in every C++ implementation. So I've kept to the standards. ;)

>Now let's hear your reasoning.
1 part laziness, 1 part sadistic intentions, and 2 parts obscure standards interpretation. I do it because I don't like to deal with VC++6's problems while compiling with multiple compilers, and I like to shoot down arguments against a seemingly non-standard style. ;)

>>This makes things like printf calls look funny.

Well printf calls already look funny in my opinion...cout is prettier :D

I guess I can't argue with you though...

>Well printf calls already look funny in my opinion...cout is prettier
A matter of opinion to be sure. But I don't usually use C streams in C++ for the sake of good style and because they mesh awkwardly with std::strings.

Thanks for your help:
I've almost got my programme (btw is it programme or program??) working (haven't had much time to work on it :@)

P.S:

Quote:

---

...I bet she was using Dev-C++.....

---

'She' = me
Me = Wiramu
Wiramu = a 'he'
confused?
Good! 'Cos I'm wiramu, and I'm a dude!
o_0

PPS: Im using MS VS version7
;D

Quote:

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Originally posted by Prelude
The C++ standard gives us the c* headers, but it also requires conformance with standard C. This means that the C .h headers must be supported in every C++ implementation. So I've kept to the standards. ;)

---

All the C .h headers are officially listed as deprecated, so they apparently aren't going to be with us forever.

Also, C++ has never premitted all standard C code to compile; even before C99, C++ and C had different rules in a number of areas. One that comes to mind is C's automatic conversion of a void * to any other pointer type which is forbidden in C++. So I think the implication that standard C is standard C++ as well is a little misleading.

>> Good! 'Cos I'm wiramu, and I'm a dude! o_0

I was referring to Prelude, not you. Dude.

dude