A puzzle (easy one)
Koroskin Denis
2korden at gmail.com
Thu Aug 7 07:34:55 PDT 2008
On Thu, 07 Aug 2008 18:11:27 +0400, Frank Benoit
<keinfarbton at googlemail.com> wrote:
> Koroskin Denis schrieb:
>> On Thu, 07 Aug 2008 05:59:30 +0400, Frank Benoit
>> <keinfarbton at googlemail.com> wrote:
>>
>>> Wyverex schrieb:
>>>> Wyverex wrote:
>>>>> BCS wrote:
>>>>>> Reply to Koroskin,
>>>>>>
>>>>>>> Write a one-line compile-time function (or template) that returns a
>>>>>>> number, which can be written in binary as 010101010...010101.
>>>>>>> Exactly
>>>>>>> the same code should work for byte, short, int, long, cent etc.
>>>>>>>
>>>>>>> No loops or recursion allowed. Use nothing but brain! :)
>>>>>>>
>>>>>>
>>>>>> template it(T)
>>>>>> {
>>>>>> T it =
>>>>>> 0x5555_5555_5555_5555_5555_5555_5555_5555_5555_5555_5555_5555_5555_5555_5555_5555
>>>>>> & (t.max | t.min);
>>>>>> }
>>>>>>
>>>>>>
>>>>> Tried something like this, but mine and yours gives integer
>>>>> overflow...
>>>> template crazy( T )
>>>> {
>>>> T crazy = 0xAAAA_AAAA_AAAA_AAAA;
>>>> }
>>>> as long as the hex string is less then ulong.max ... or ucent.max
>>>> when that gets implemented...
>>>
>>> template func( T ) { T func = mixin( "0x555555555555555555555555"[0 ..
>>> T.sizeof*2+2] ); }
>> No-no-no. It should work for integer type of *any* length (byte,
>> short, long, cent and any future type).
>> And there is a *much* simpler solution!
>
> right.
> template func( T ) { T func = T.max/3; }
Doesn't work for signed types :P
But you are close!
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