RE: [Dev-C++] reg-Knight's tour problem

[Santiago P. C. <San...@yd...>]

Hi Mohammed,

Let me try to give some help on this issue O:o)

A 'common' recursive algorithm looks like this one:

// Calculate factorial of int number
int recursive_function(int iParameter)
{
	// Check for posible errors
	if (iParameter < 0)
	{
		cout << "ERROR: Negative number!" << endl;
		exit(SOME_ERROR_VALUE);
	}

	// Check race condition
	if (iParameter == 0)
	{
		// We got it! No more loops ;o)
		return 1;
	}
	else
	{
		// Handle params & manage with values
		int iCurrentValue = iParameter;
		iParameter--;

		return (iCurrentValue*recursive_function(iParameter));
	}
}

This is not THE answer, it's a simple function to ilustrate recursive
algorithms, there are variants depending on the desired behaviour of the
function (p.e. you can handle parameter/s before checking the race
condition).

The point here is that you must reach the race condition inside the function
and terminate the program normally, if you don't do that you'll exit the
program 'the hard way' even when the program itself succeeds.

As a good programming practice you should try to avoid exiting abruptly,
instead of this, you should perform any necessary cleanup tasks when you
exit a program p.e.: close open files, deallocate reserved memory, etc...

Hope this helps!

Best regards, Santy


-----Original Message-----
From: Mohammed Riyaz [mailto:p_m...@ho...] 
Sent: Thursday, March 07, 2002 5:05 PM
To: dev...@li...
Subject: RE: [Dev-C++] reg-Knight's tour problem


hey ioannis;
The variables i,j are members of the class. Why do you say recursion never 
end. The function assignment calls the other functions 'refresh', 'value' in
the line

refresh();
pos=value(j+(8*i));

hence when the this situation (given below)arises in the function value, the

program wil hald and hence the recursion ends there.

if(row_loc<0) {cout<<"NO SOLUTION";system("pause");exit(0);}

(or)

when the situation
if(l==63)
                          {
                          cout<<"RESULT :"<<endl;
                          for(int k=0;k<64;k++)
                               cout<<denied[k]<<" ";
                          system("pause");
                          exit(0);
                          }
in refresh function is encountered the recursion ends.
-Riyaz

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