std.random

[Kramer]

In article <pjctg3-8g7.ln1 at birke.kuehne.cn>, Thomas Kuehne says...
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>Charles schrieb am 2006-04-11:
>> Charles wrote:
>>> How do i get a number in the range -0.5 to 0.5 ?
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>const float RAND_MAX = uint.max;
>float sum = 0.0;
>for(size_t i = 1; i < 101; i++){
>    float x = (rand() / RAND_MAX) - 0.5;
>    sum += x;
>    writefln("round:%s\t%s\t(%s)", i, x, sum / i);
>}
>
>Thomas
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Forgive me for asking such a naive (I feel I should know this already) question
and taking this off-topic, but what is the type size_t?  I've seen it used (and
also ptrdiff_t I believe), but I don't know what they're for or how to use them?

-Kramer