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simple while loop

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Join Date: Feb 2008

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free2rhyme2k free2rhyme2k is offline

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simple while loop

Feb 1st, 2008

Hi there

I am writing a simple while loop which terminates on the condition that a certain value is found, as follows

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std::string question = q.quest().que();
            std::string answer = q.ans().answer();
            std::string graphic = q.inf().info();
            std::string english1;
            std::string english2;
            std::string arabic1;
            std::string arabic2;
 
 
            while((answer != english1) || (answer != english2)) { 
                       random_shuffle(opt.begin(),opt.end()); 
                            english1 = opt[0].english();
                            arabic1 = opt[0].arabic();
                            english2 = opt[1].english();
                            arabic2 = opt[1].arabic();
            }
std::string question = q.quest().que();
            std::string answer = q.ans().answer();
            std::string graphic = q.inf().info();
            std::string english1;
            std::string english2;
            std::string arabic1;
            std::string arabic2;
           
            
            while((answer != english1) || (answer != english2)) { 
                       random_shuffle(opt.begin(),opt.end()); 
                            english1 = opt[0].english();
                            arabic1 = opt[0].arabic();
                            english2 = opt[1].english();
                            arabic2 = opt[1].arabic();
            }

The program gets stuck in the while loop. I guess this is some sort of error in the while loops condition. If I take out the second condition and make it just based upon “English1”, then it works fine.

Any help?

Thanks in advance

Last edited by WaltP; Feb 2nd, 2008 at 12:09 am. Reason: Fixed CODE tags -- try the PREVIEW button before SUBMITting

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VernonDozier VernonDozier is offline

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Re: simple while loop

Feb 1st, 2008

english1 and english2 don't appear to be initialized. Also, in this line:

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while((answer != english1) || (answer != english2))
while((answer != english1) || (answer != english2))

you are comparing answer to the addresses, not the contents of the variables english1 and english2. String comparisons don't work the way integer comparisons do. Instead of using == or != you usually use the "compare" function from the string library if you want to compare the contents of strings rather than the addresses.

http://www.cplusplus.com/reference/s...g/compare.html

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WaltP

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Re: simple while loop

Feb 2nd, 2008

 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
while((answer != english1) || (answer != english2)) {
while((answer != english1) || (answer != english2)) {