-
September 24th, 2013, 07:00 AM
#16
Re: Please find the bug in the c++ code
When I debugged it after removing comments , I got like this in the command window:
DEBUG2: m = 3 i = 0
{f} = 2 {u} 2
DEBUG2: m = 2 i = 0
The bug is exactly here at the end of the CheckPoss function, because the value of 'm' should not decrease .
-
September 24th, 2013, 07:17 AM
#17
Re: Please find the bug in the c++ code
Hi OReubens,
I did like you told.I got a code like this:
Code:
throw -- terminate on thrown exception REPLACEABLE
#define _HAS_EXCEPTIONS 0
#include <cstdio>
#include <cstdlib>
#include <exception>
#include <crtdbg.h>
_STD_BEGIN
#ifdef _DEBUG
_CRTIMP2_PURE void __CLRCALL_PURE_OR_CDECL _Debug_message(const wchar_t *message, const wchar_t *file, unsigned int line)
{ // report error and die
if(::_CrtDbgReportW(_CRT_ASSERT, file, line, NULL, message)==1)
{
::_CrtDbgBreak();
}
}
_CRTIMP2_PURE void __CLRCALL_PURE_OR_CDECL _Debug_message(const unsigned short *message, const unsigned short *file, unsigned int line)
{ // report error and die
_Debug_message((wchar_t *) message, (wchar_t *) file, line);
}
#endif
_STD_END
-
September 24th, 2013, 07:39 AM
#18
Re: Please find the bug in the c++ code
The specific problem is this:
This is the BASIC code of CheckPoss function:
Code:
FUNCTION CheckPoss (u)
tot = tot + 1
f = 0
SELECT CASE u
CASE 2
f = f + CheckIntersection(1, 3, 2, 1) 'A
CASE 3
f = f + CheckIntersection(1, 3, 2, 1) 'A
f = f + CheckIntersection(2, 3, 3, 1) 'B
CASE 4
f = f + CheckIntersection(1, 3, 2, 1) 'A
f = f + CheckIntersection(2, 3, 3, 1) 'B
f = f + CheckIntersection(1, 4, 4, 2) 'C
CASE 5
f = f + CheckIntersection(1, 3, 2, 1) 'A
f = f + CheckIntersection(2, 3, 3, 1) 'B
f = f + CheckIntersection(1, 4, 4, 2) 'C
f = f + CheckIntersection(2, 4, 5, 2) 'D
f = f + CheckIntersection(4, 3, 5, 1) 'F
CASE 6
f = f + CheckIntersection(1, 3, 2, 1) 'A
f = f + CheckIntersection(2, 3, 3, 1) 'B
f = f + CheckIntersection(1, 4, 4, 2) 'C
f = f + CheckIntersection(2, 4, 5, 2) 'D
f = f + CheckIntersection(3, 4, 6, 2) 'E
f = f + CheckIntersection(4, 3, 5, 1) 'F
f = f + CheckIntersection(5, 3, 6, 1) 'G
CASE 7
f = f + CheckIntersection(1, 3, 2, 1) 'A
f = f + CheckIntersection(2, 3, 3, 1) 'B
f = f + CheckIntersection(1, 4, 4, 2) 'C
f = f + CheckIntersection(2, 4, 5, 2) 'D
f = f + CheckIntersection(3, 4, 6, 2) 'E
f = f + CheckIntersection(4, 3, 5, 1) 'F
f = f + CheckIntersection(5, 3, 6, 1) 'G
f = f + CheckIntersection(4, 4, 7, 2) 'H
CASE 8
f = f + CheckIntersection(1, 3, 2, 1) 'A
f = f + CheckIntersection(2, 3, 3, 1) 'B
f = f + CheckIntersection(1, 4, 4, 2) 'C
f = f + CheckIntersection(2, 4, 5, 2) 'D
f = f + CheckIntersection(3, 4, 6, 2) 'E
f = f + CheckIntersection(4, 3, 5, 1) 'F
f = f + CheckIntersection(5, 3, 6, 1) 'G
f = f + CheckIntersection(4, 4, 7, 2) 'H
f = f + CheckIntersection(5, 4, 8, 2) 'I
f = f + CheckIntersection(7, 3, 8, 1) 'K
CASE 9
f = f + CheckIntersection(1, 3, 2, 1) 'A
f = f + CheckIntersection(2, 3, 3, 1) 'B
f = f + CheckIntersection(1, 4, 4, 2) 'C
f = f + CheckIntersection(2, 4, 5, 2) 'D
f = f + CheckIntersection(3, 4, 6, 2) 'E
f = f + CheckIntersection(4, 3, 5, 1) 'F
f = f + CheckIntersection(5, 3, 6, 1) 'G
f = f + CheckIntersection(4, 4, 7, 2) 'H
f = f + CheckIntersection(5, 4, 8, 2) 'I
f = f + CheckIntersection(6, 4, 9, 2) 'J
f = f + CheckIntersection(7, 3, 8, 1) 'K
f = f + CheckIntersection(8, 3, 9, 1) 'L
END SELECT
IF f = 0 THEN
CheckPoss = 1
IF u = 9 THEN
PrintSolution
END IF
END IF
END FUNCTION
The c++ equivalent is :
Code:
int CheckPoss (int u) {
tot = tot + 1;
int f = 0;
int ret = 0 ;
switch (u) {
case 1:
f = f + CheckIntersection(0,2,1,0); //'A
break;
case 2:
f = f + CheckIntersection(0,2,1,0); // 'A
f = f + CheckIntersection(1,2,2,0); // 'B
break;
case 3:
f = f + CheckIntersection(0,2,1,0) ; // 'A
f = f + CheckIntersection(1,2,2,0) ; // 'B
f = f + CheckIntersection(0,3,3,1) ; // 'C
break;
case 4:
f = f + CheckIntersection(0,2,1,0) ; // 'A
f = f + CheckIntersection(1,2,2,0) ; // 'B
f = f + CheckIntersection(0,3,3,1) ; // 'C
f = f + CheckIntersection(1,3,4,1) ; // 'D
f = f + CheckIntersection(3,2,4,0) ; // 'F
break;
case 5:
f = f + CheckIntersection(0,2,1,0) ; // 'A
f = f + CheckIntersection(1,2,2,0) ; // 'B
f = f + CheckIntersection(0,3,3,1) ; // 'C
f = f + CheckIntersection(1,3,4,1) ; // 'D
f = f + CheckIntersection(2,3,5,1) ; // 'E
f = f + CheckIntersection(3,2,4,0) ; // 'F
f = f + CheckIntersection(4,2,5,0) ; // 'G
break;
case 6:
f = f + CheckIntersection(0,2,1,0) ; // 'A
f = f + CheckIntersection(1,2,2,0) ; // 'B
f = f + CheckIntersection(0,3,3,1) ; // 'C
f = f + CheckIntersection(1,3,4,1) ; // 'D
f = f + CheckIntersection(2,3,5,1) ; // 'E
f = f + CheckIntersection(3,2,4,0) ; // 'F
f = f + CheckIntersection(4,2,5,0) ; // 'G
f = f + CheckIntersection(3,3,6,1) ; // 'H
break;
case 7:
f = f + CheckIntersection(0,2,1,0) ; // 'A
f = f + CheckIntersection(1,2,2,0) ; // 'B
f = f + CheckIntersection(0,3,3,1) ; // 'C
f = f + CheckIntersection(1,3,4,1) ; // 'D
f = f + CheckIntersection(2,3,5,1) ; // 'E
f = f + CheckIntersection(3,2,4,0) ; // 'F
f = f + CheckIntersection(4,2,5,0) ; // 'G
f = f + CheckIntersection(3,3,6,1) ; // 'H
f = f + CheckIntersection(4,3,7,1) ; // 'I
f = f + CheckIntersection(6,2,7,0) ; // 'K
break;
case 8:
f = f + CheckIntersection(0,2,1,0) ; // 'A
f = f + CheckIntersection(1,2,2,0) ; // 'B
f = f + CheckIntersection(0,3,3,1) ; // 'C
f = f + CheckIntersection(1,3,4,1) ; // 'D
f = f + CheckIntersection(2,3,5,1) ; // 'E
f = f + CheckIntersection(3,2,4,0) ; // 'F
f = f + CheckIntersection(4,2,5,0) ; // 'G
f = f + CheckIntersection(3,3,6,1) ; // 'H
f = f + CheckIntersection(4,3,7,1) ; // 'I
f = f + CheckIntersection(5,3,8,1) ; // 'J
f = f + CheckIntersection(6,2,7,0) ; // 'K
f = f + CheckIntersection(7,2,8,0) ; // 'L
break;
}
if (f == 0) {
ret = 1;
if (u == 8) {
PrintSolution();
}
}
cout << " {f} = " << f << " {u} " << u << endl;
if (f != 0) ret = 0;
return ret;
}
Please do not worry about the different values inside CheckIntersection function..It arises due change in counting from 1 to 0. I am not sure if what I have written at the end of the c++ function is correct.
-
September 24th, 2013, 08:07 AM
#19
Re: Please find the bug in the c++ code
You don't seem to understand what's meant by debugging. Using the debugger you can run your program, interrupt execution at any point using breakpoints, examine the values of any variables, follow the execution line by line, use the call stack to find out how you got where you are in the code, change values, set the next line of execution and all kinds of fun stuff. Nobody's talking about using ifdefs. You need to learn how to use the debugger that comes with whatever compiler you're using.
-
September 24th, 2013, 08:12 AM
#20
Re: Please find the bug in the c++ code
At GCDEF,
you are absolutely correct. I will try to use the debugger to interrupt execution and follow execution and to do all the fun stuff.
Regards.
-
September 24th, 2013, 09:49 AM
#21
Re: Please find the bug in the c++ code
The correct solution still eludes me. Every thing seems to work correct . I tried debugging line by line too. The method tries to search the correct combination by backtracking method. So even after fitting say 5 pieces , if it is not possible to find the correct piece , it backtracks. But, it backtacks fully and stops searching for new pieces that fit exactly.
thanks, navy
-
September 24th, 2013, 10:06 AM
#22
Re: Please find the bug in the c++ code
Originally Posted by navy1991
The correct solution still eludes me.
if it is not possible to find the correct piece , it backtracks. But, it backtacks fully and stops searching for new pieces that fit exactly.
So why does it backtrack fully? Why does it stop searching for pieces that fit exactly?
The answer is not "I don't know" -- it should be "I will debug to see where the fault is in the logic".
Lastly, why not start out with a simpler test? Why do you need to jump in and try all of these pieces? How about just 4 pieces, or 3 pieces? Then you can follow the code (using the debugger) much easily with a simpler example. Then when you get the simpler version working, you then apply that to more pieces.
Regards,
Paul McKenzie
-
September 24th, 2013, 04:44 PM
#23
Re: Please find the bug in the c++ code
I suspect that part of the problem is due to array bounds issue. eg in printsolution() the loop is <= 8 when it should be < 8. This could be repeated through the code. Has all of the code been converted from Basic or just the function checkpos()? If all has been converted, I suggest you start again from the original code, size the arrays way too big for what you want and assume the index starts at 1. Get this code to work then deal with moving the index to start at 0 rather than start at 1. Also I would suggest using a meaninful const int for the array dimensions and 'magic numbers' in the code rather than have numbers like 8, 3, 1 etc scattered about the code. Also check the use of <= and confirm this is what is meant and not just <.
All advice is offered in good faith only. All my code is tested (unless stated explicitly otherwise) with the latest version of Microsoft Visual Studio (using the supported features of the latest standard) and is offered as examples only - not as production quality. I cannot offer advice regarding any other c/c++ compiler/IDE or incompatibilities with VS. You are ultimately responsible for the effects of your programs and the integrity of the machines they run on. Anything I post, code snippets, advice, etc is licensed as Public Domain https://creativecommons.org/publicdomain/zero/1.0/ and can be used without reference or acknowledgement. Also note that I only provide advice and guidance via the forums - and not via private messages!
C++23 Compiler: Microsoft VS2022 (17.6.5)
Tags for this Thread
Posting Permissions
- You may not post new threads
- You may not post replies
- You may not post attachments
- You may not edit your posts
-
Forum Rules
|
Click Here to Expand Forum to Full Width
|