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Pls don't worry.
This is what I wrote and got the (correct) result:
void CMyHexDDlg::Temp()
{ CString result;
unsigned _int64 ui64Max=Limits<unsigned _int64="">::Max();
result.Format("Max:%I64u",ui64Max);
AfxMessageBox(result);
_int64 i64Min=Limits<_int64>::Min();
result.Format("Min:%I64i",i64Min);
AfxMessageBox(result);
char cMin=Limits<char>::Min();
result.Format("Min:%i",cMin);
AfxMessageBox(result);
}
///////////////////////////////////////////
The output of the three message boxes is:
Max: 18446744073709551615
Min: -9223372036854775808
Min:-128
The code is very subtle and very interesting.
May I add that you are a supestar alright.
Thank you so much for your time and effort.
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I have difficulty with one part of this statement and I hope you give me a hand there.
static T Max()
{ return (T)~0 > 0 ? (T)~0 : (T)~0 & ~((T)1 << (sizeof(T) * 8 - 1)); }
/////////////////////////////////////////
Say I have a WORD:
00000000 00000000
If it is a UWORD (HOB set to 1) return
11111111 11111111
If it is a WORD (HOB set to -)
transform it to
11111111 11111111
and AND it with what exactly ?
Bearing in mind that: 1<< (sizeof(T)*8-1) is:
10000000 00000000
Thanks for any help.
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http://www.codeproject.com/cpp/bitbashing.asp[^]
In a signed value the high order bit(HOB) is the sign bit, it is zero for positive numbers and one for negative numbers. In unsigned values the HOB has no special significance.
So what is done is to first check if we are dealing with a signed or unsigned value by checking if ~0 (inverse zero) is greater than zero. For signed values ~0 will give you -1 (minus one), for unsigned values it will give you the largest possible value.
So for unsigned values we can simply return ~0.
But for signed values, we have to clear the HOB (set it zero) to get the largest possible value
ie:
BYTE bMax = Limits<BYTE>::Max();
will do the following calculations:
(T)~0 > 0 ?
00000000 inversed is 11111111
is 11111111 greater than zero?
No, it is minus one, so it is less than zero.
So we have to return: (T)~0 & ~((T)1 << (sizeof(T) * 8 - 1))
00000000 inversed is 11111111
00000001 left shifted 1 * 8 - 1 (or 7) is 10000000
10000000 inversed is 01111111
11111111 bitwise and 01111111 is 01111111
So we can return 01111111, the largest possible signed value.
And now that I have gone through the exercise of explaining it this way, I realize that I can simplify the function a little. The last step with the bitwise and can be eliminated. The function can be
static T Max() { return (T)~0 > 0 ? (T)~0 : ~((T)1 << (sizeof(T) * 8 - 1)); }
Thanks for putting me through this exercise
"You're obviously a superstar." - Christian Graus about me - 12 Feb '03
"Obviously ??? You're definitely a superstar!!!" mYkel - 21 Jun '04
Within you lies the power for good - Use it!
Honoured as one of The Most Helpful Members of 2004
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I am really thankfull fo your time,experience and generousity.
My mistake is that I missed the fact that the NOT(~) opeator inverses the bits state.
So applying it to : 10000000 00000000
The Operand becomes: 01111111 11111111
That AND_ ed with : 11111111 11111111
becomes : 01111111 11111111
(whic is 32767 decimal)
I learnt many very useful tricks with you.
Thank you sooooooooooo muuuuuuuuuuuuuuuuuuch.
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Hi
A client server application that uses Winsock2 for communication.
Q1.
Is a single recv() in response to a single FD_READ message appropriate OR the
recv() must be called in a loop untill all data is received.
Q2.
Lets say the server needs to send 1000 bytes of data to the client but at a time
only 100 bytes.
Now there are two ways:
1----> The server calls send() in a loop & donot cares whether data reaches the client or not.
2----> The server calls send() in a loop & after every send() it waits for the client's
notification that the data is received, now send next lot of 100 bytes.
Waiting for suggestions
Best Regards
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A1. you have do continuously received the data in loop.
A2. You should be aware of which format server (syn or asyn) is sending the data and respond accordingly by checking the data termination condition.
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The server is an asynchronous server.
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Hi,
I am using Visual studio .NET 2002. Sometimes when I try opening a cpp file, my Visual studio seems to be hanging. It will take 7-8 mins to open the file.
SO what I usually do is I will delete the .ncb file (the database file for the solution).
Then the performance will be good enough at the cost of not getting the drop downs in the editor (list of methods, data members etc).
Any ideas as to why should it hang?
Thanks
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PrashantJ wrote:
Any ideas as to why should it hang?
You require more Memory in your Computer!
"Opinions are neither right nor wrong. I cannot change your opinion. I can, however, change what influences your opinion." - David Crow
cheers,
Alok Gupta
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Upgrade to microsoft less hanging version, like Visual Studio 6.0
My idea is to create a new project by wizard (not a empty one) and remove the cpp and h from it, and add your files to the project. And then compile the project. Just try it, it works many times for me.
http://www.priyank.in/
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Hey all,
I am new to this forum. Wish I was good at programming , so i cud have posted the solutions...unfortunately, I am not...Instead I have my own query....and am desperately seeking help...
I have this assignment submission next week. I have no idea about the logic for this assignment. My assignment is as follows:
*********************************************
Text segmentation from images with scenery + text. Obtain at least 10 images from newspapers, magazines etc. Some should be color. (3 min) Scan them as necessary. Devise three segmentation techniques to separate letters from background. Methods should be essentially automatic in operation. Methods: may include :Thresholding Local or Global, Color. Geometric Features, Texture
*************************************************
Can anyone help me out with the logic for this program? This thing is in C++. All I have done is binarise the input image.But I dont know how to proceed. Please help me out guys.
Cheers,
Raj
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I write a console program that connect 2 computers with socket, like a chat program. I try to use the commands that use windows socket v1.1 only because I don't sure Windows NT Server 3.51 support windows socket v2 or not. When I test with 2 Windows XP, it works very well. But when I test with a Windows XP and a Windows NT Server 3.51, It doesn't work both Windows XP be a server and a client. Client side tells me "Could not get host by address", but no run time error.
I think the problem is compiling. I don't know how to do. Please give me some suggestions about setting the compiler or the other method to solve this problem. Thank you very much.
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Does anyone here want an article explaining how to write a 2D graphics game engine using DirectX 9? I don't have alot of time but if someone wants I can spare some time to write an article. Need a reply if you want me to make the article.
IM PROUD TO BE A GMAIL;
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Dirext X is a pretty hard field atleast for me, and if you can write articles on it, every body would be interested on it. B'caz articles are not shown here for a day, so future members of CP can also got the benefit of your expertise.
tom_dx wrote:
don't have alot of time
No body at CP have time, all are big programmers, but to write an article is a way to increase your knowledge also about that subject.
My request on Direct X is a very simple article for that can be understand by fools like me, and covers the advanced details of Direct X on capturing video from various sources, like multiples camera, desktops, etc.
http://www.priyank.in/
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tom_dx wrote:
Need a reply if you want me to make the article
Reply you want, Reply you get
"Opinions are neither right nor wrong. I cannot change your opinion. I can, however, change what influences your opinion." - David Crow
cheers,
Alok Gupta
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Yes, please write the article.
If you could get a slant towards 2D graphics that won't be used as a game.
1) alpha blending
2) lockable framerate so that in a non-game application it doesn't use 100% cpu
I could go on.
I tried doing some 2D stuff in DX9 but went back to DX7 since you can still get an HDC to the surface and draw to it that way.
BTW by interst is in doing graphics for an HTPC.
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An integer variable in an application is overwritten somehow, but I do not have a clue as to where it is occurring.
how ca I best use the integrated debugger to track this kind of problem down?
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These kind of things happen due to buffer overflow.
To find out where this is happening, why don't you put a breakpoint condition, to break when the value of that variable changes.
You can set this break point from the breakpoints dialog box in VC++6.
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hi
i had the problem in my application.i had made the library and include in the project from menu(project->addtotheproject->files) it workds perfectaly for the debug and release builds only for "use mfc shared dll" more below.
But, from the (project->settings) menu when i choose the 'use MFC in the static library' in the drop down list of "microsoft foundation classes" it gives the errors which are
msvcrt.lib(MSVCRT.dll) : error LNK2005: __setmbcp already defined in libcmtd.lib(mbctype.obj)
LINK : warning LNK4098: defaultlib "mfc42.lib" conflicts with use of other libs; use /NODEFAULTLIB:library
LINK : warning LNK4098: defaultlib "mfcs42.lib" conflicts with use of other libs; use /NODEFAULTLIB:library
LINK : warning LNK4098: defaultlib "msvcrt.lib" conflicts with use of other libs; use /NODEFAULTLIB:library
Debug/CH3.exe : fatal error LNK1169: one or more multiply defined symbols found
Error executing link.exe.
CH3.exe - 2 error(s), 3 warning(s)
can anybody tell me what to do.
ddd
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Your statically linked library should use the same MFC model as your application.
You could MAYBE get away with the statically linked library using MFC as static, but you have to add special macros at the beginning of each function. You probably won't get the program to run correctly if you mix a static link library built using MFC as shared with an application built using MFC as static.
Go reset the setting for your static link library to match those of your EXE.
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my statically linked library is using the same MFC model.i had build the library using the "use mfc as static library" from the prject setting menu. there are no errors or warnings in that.
but still it gives the same errors as i stated earlier.
ddd
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It seems you have the debug library linked with the release exe or vice versa.
Make sure you did not include the debug version of your library instead of the release version with the release version of your program.
The "libcmtd.lib" makes me think you got the debug version associated with the other libraries which are release versions.
I think that name roughly translates as "Library C Multi-Threaded? Debug".
Which also reminds me, if your program is going to be multi-threaded, make sure your libraries are set to be multi-threaded as well.
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i first "build" the library using debug as option and then build the library using the release as option.
in my application where i had used the library is .lib file present in release folder,and then i build my application which gives errors.
tell me what that problem is.
my application is not multithreaded.
ddd
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