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Jun 15th, 2009
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need help with calculations

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hello this code seems to give me wrong results and i carnt figure out why

C++ Syntax (Toggle Plain Text)
  1. #include <iostream>
  2. int main() {
  3.  
  4.     float pi = 3.142;
  5.     char area;
  6.     float diameter;
  7.  
  8.     area = diameter * pi;
  9.  
  10.     std::cout << "Hello. Please imput the diameter of your circle... ";
  11.     std::cin  >> diameter;
  12.  
  13.     std::cout << "The area of your circle is " << 'area' << ".\n";    
  14.     std::cin.get();
  15.     return 0;
  16. }
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slawted is offline Offline
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Jun 15th, 2009
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Re: need help with calculations

Fill a glass with water (or what else) then drink, not vice versa

Calculate a circle area AFTER its diameter request.
Output the area variable, not a wrong character literal 'area'...
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ArkM is offline Offline
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Re: need help with calculations

C++ Syntax (Toggle Plain Text)
  1. #include <iostream>
  2. int main() {
  3.  
  4.     float pi = 3.142;
  5.     char area;
  6.     float diameter;
  7.  
  8.     std::cout << "Hello. Please imput the diameter of your circle... ";
  9.     std::cin  >> diameter;
  10.  
  11.     area = diameter * pi;
  12.  
  13.     std::cout << "The area of your circle is " << area;    
  14.     std::cin.get();
  15.     return 0;
  16. }

gives me a wierd symbol for the area? why is this i cannot see anything wrong with my code (newbie)
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slawted is offline Offline
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Jun 15th, 2009
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Re: need help with calculations

>gives me a wierd symbol for the area?
area is declared as a char, and cout is assuming you want to print a character rather than the integral value. Change char area; to int area; and you'll get a slightly more reasonable result.
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Narue is offline Offline
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Jun 15th, 2009
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Re: need help with calculations

Thank you that has gave me a realistic result but it doesnt show the deicmals just rounds it to a whole number ? is there anyway to let it do this thank you once again
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Re: need help with calculations

and to stop the program flashing of the screen?
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Re: need help with calculations

>...why is this i cannot see anything wrong with my code...
Oh, this harmful Daniweb engine! I see 'area' in the OP snippet but area in the post #3 code
By the way, change char area; to float area; ...
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ArkM is offline Offline
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Re: need help with calculations

Woop everything works fine now, except the program flashes off straight away lol ? should std::cin.get(); stop that happening?
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Re: need help with calculations

anyone?
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slawted is offline Offline
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Re: need help with calculations

Insert std::cin.ignore(1000,'\n'); after std::cin >> diameter;
Last edited by ArkM; Jun 15th, 2009 at 3:45 pm.
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