Re: [Warning] converting to `unsigned int' from `double';

"Alf P. Steinbach" <>
Sat, 09 Jan 2010 23:51:13 +0100
* er:


How do I get rid of the warning below without changing the type of n,
while keeping the scientific format? Is static_cast<unsigned>(5e4) the
only way?

const unsigned n = 5e4; // [Warning] converting to `unsigned int' from

I use : Win7-32 V6.1.7100 Dev-C++ 5.0 beta 9.2 with Mingw/GCC 3.4.2

You shouldn't use 'unsigned' for other than bit level manipulation.

The standard library does, for historical reasons, and it sucks.

Ignoring that very good advice (which if you're a smart man is what you should
pay heed to), to just get rid of the warning (brainless dog's or copy-cat's

   unsigned const n = unsigned( 5e4 );

One reply else-thread recommends static_cast. In this context using static_cast
is meaningless, for there's no chance at all that the type involved will change.
But using unsigned is of course infinitely more silly, so just don't do it.

Another reply else-thread suggests that 5e4 may not exactly represent 50000 on
all C++ implementations. But there's no need to be concerned about that: no
actually used floating point representation fails to represent 50000 exactly,
and no future floating point representation will fail. On the other hand, do
think about doing things like

   int const n = 50*1000;

Cheers & hth.,

- Alf

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