Hey people, I was just wondering if someone could help me with some code. I need to round a number off to the nearest multiple of 5 and i can't figure out how to do it. If you can help it would be much appreciated if you could tell me asap please. Thanks
Re: urgent
Think about how you'd do it without a computer. I'd probably divide the number by 5 and note the remainder. Then I'd subtract the number from the remainder.
If I did your homework for you, then you might pass your class without learning how to write a program like this. Then you might graduate and get your degree without learning how to write a program like this. You might become a professional programmer without knowing how to write a program like this. Someday you might work on a project with me without knowing how to write a program like this. Then I would have to do you serious bodily harm. - Jack Klein
writing out a plan on paper is key
this is how I just thought of
Code:#include<iostream> int main() { int number = 13556; int temp; temp = number/5; number = number - (number - temp*5); std::cout << number; }
To shortern the code a bit.
Code:#include<iostream> //13555 int main() { int number = 13556; number -= number % 5; std::cout << number; }
Thanks heaps, also does anyone know how to do it with a float? I need to take a float (number1) and round it off to the nearest multiple of 5 which will then be presented as number2.
Last edited by Razakel; 03-21-2006 at 09:18 PM.
That method will work for a float, just convert it to an int first (Since presumably you're not expecting any significant figures after the decimal point if it's a multiple of 5...)
Warning: neither of the posted methods will do what you said you wanted.I need to round a number off to the nearest multiple of 5 and i can't figure out how to do it.
True, to use a more 'mathematically correct' approach, an extra step is needed to check the halfway rounding point.Originally Posted by 7stud
Code:#include <iostream> int main() { const int number = 13; const int multiple = 5; int result=number-(number%multiple); if ( (number%multiple) > ((float)multiple/2) ) result+=multiple; std::cout << result; std::cin.get(); }
This will work too, 4 examples, two with int and two with float showing both rounding up and down
Code:#include <iostream> int main() { int number = 13557; std::cout << 5 * ((2 + number )/5 ) << "\n"; int number2 = 13558; std::cout << 5 * ((2 + number2 )/5 ) << "\n"; float number3 = 13557.481; std::cout << 5 * (int(2.5 + number3 )/5) << "\n"; float number4 = 13557.781; std::cout << 5 * (int(2.5 + number4 )/5) << std::endl; }
Last edited by Darryl; 03-22-2006 at 09:49 AM.
How about some C++ casting syntax as well as code that won't produce cast warnings(VC++6)?
I wasn't pointing out some mathematical technicality. 'round' has a common sense, intuitive meaning, and when someone asks you to round 14 to the nearest multiple of 5, they would not expect the result to be 10.True, to use a more 'mathematically correct' approach,
Last edited by 7stud; 03-22-2006 at 12:26 PM.
I don't know. Are we just reading it differently?'round off' also has a common sense, intuitive meaning.
If I did your homework for you, then you might pass your class without learning how to write a program like this. Then you might graduate and get your degree without learning how to write a program like this. You might become a professional programmer without knowing how to write a program like this. Someday you might work on a project with me without knowing how to write a program like this. Then I would have to do you serious bodily harm. - Jack Klein
You could rephrase it in plenty of different ways, "round up", "round down", "round off", etc. I don't think the OP was quite expecting that sort of nitpicking though, but there's enough examples of both here. Whether he/she wants, for example, 19 to "rounded" to 20 or to 15.'round off' also has a common sense, intuitive meaning.
Fair comment, it was a bit of laziness. I'm not sure why you got the warnings (compiling in strict/pedantic mode?), both comeau and VC++2003 quietly accepted the C-cast anywayHow about some C++ casting syntax as well as code that won't produce cast warnings(VC++6)?
Updated with C++ cast. Hopefully without warnings on VC6.Code:#include <iostream> int main() { const int number = 13; const int multiple = 5; int result=number-(number%multiple); if ( (number%multiple) > (static_cast<float>(multiple)/2.0) ) result+=multiple; std::cout << result; std::cin.get(); }
First hit on google for 'round off':
http://www.gomath.com/algebra/round.phpRound off 39.18769 to the nearest thousandth.
39.18769 = 39.188
Last edited by 7stud; 03-22-2006 at 05:00 PM.
LoL...touche!
If I did your homework for you, then you might pass your class without learning how to write a program like this. Then you might graduate and get your degree without learning how to write a program like this. You might become a professional programmer without knowing how to write a program like this. Someday you might work on a project with me without knowing how to write a program like this. Then I would have to do you serious bodily harm. - Jack Klein
